Reproductive System

Chapter: Male Reproductive System; Topic: Penis; Subtopic: Structure & Anatomical Continuity

Keyword Definitions:

• Corpus Spongiosum: Erectile tissue surrounding the penile urethra and forming the glans penis.

• Corpora Cavernosa: Paired erectile bodies forming most of the penile shaft except the glans.

• Glans Penis: Expanded distal end of the corpus spongiosum.

• Urethra: Tube conducting urine/semen, enclosed in corpus spongiosum.

• Buck’s Fascia: Deep fascia binding erectile tissues together.

1) Lead Question – 2016
Glans penis is a continuation of -
a) Corpus spongiosum
b) Ischiocavernosus
c) Corpora Cavernosa
d) Puborectalis

Answer: a) Corpus spongiosum

Explanation: The glans penis represents the expanded distal part of the corpus spongiosum. The spongiosum encloses the penile urethra and continues distally to form the glans. The corpora cavernosa do not extend into the glans; instead, they terminate proximally to it. Ischiocavernosus is a perineal muscle acting on the crura of cavernosa, and puborectalis is part of the pelvic floor, unrelated to penile anatomy. Thus, the correct continuation of glans penis is the corpus spongiosum.

2) Corona of glans penis represents?
a) Margin between shaft and glans
b) Frenulum
c) External urethral meatus
d) Raphe

Answer: a) Margin between shaft and glans

Explanation: The corona forms the projecting ridge marking the junction of glans with the penile shaft.

3) Which fascia forms the deep fascia of penis?
a) Colles fascia
b) Buck’s fascia
c) Camper’s fascia
d) Dartos fascia

Answer: b) Buck’s fascia

Explanation: Buck’s fascia encases corpora cavernosa and spongiosum and maintains penile shape.

4) Penile urethra is enclosed in?
a) Corpus spongiosum
b) Corpora cavernosa
c) Suspensory ligament
d) Ischiocavernosus

Answer: a) Corpus spongiosum

Explanation: The spongiosum houses the urethra throughout its penile course.

5) Glans receives arterial supply from?
a) Dorsal artery of penis
b) Deep artery of penis
c) External pudendal artery
d) Inferior epigastric artery

Answer: a) Dorsal artery of penis

Explanation: The glans and prepuce are supplied mainly by dorsal penile arteries.

6) A child presents with penile swelling; Buck’s fascia is ruptured. Urine spreads to?
a) Abdomen deep to Scarpa’s fascia
b) Perineum superficial pouch
c) Thighs
d) Pelvic cavity

Answer: b) Perineum superficial pouch

Explanation: With Buck’s fascia rupture, urine escapes into superficial perineal space.

7) Which nerve supplies the glans penis mainly?
a) Pudendal nerve
b) Dorsal nerve of penis
c) Perineal nerve
d) Ilioinguinal nerve

Answer: b) Dorsal nerve of penis

Explanation: Dorsal nerve, branch of pudendal, provides primary sensory supply to glans.

8) Frenulum attaches glans to?
a) Prepuce
b) Urethral sphincter
c) Scrotal skin
d) Raphe

Answer: a) Prepuce

Explanation: Frenulum is a fold anchoring prepuce to the ventral glans.

9) Erectile tissue most responsible for penile rigidity?
a) Corpus spongiosum
b) Corpora cavernosa
c) Glans penis
d) Superficial perineal fascia

Answer: b) Corpora cavernosa

Explanation: Cavernosa fill under high pressure, producing rigidity; spongiosum prevents urethral collapse.

10) Peyronie disease affects which penile structure?
a) Tunica albuginea
b) Urethral epithelium
c) Dartos muscle
d) Glans mucosa

Answer: a) Tunica albuginea

Explanation: Fibrosis of tunica albuginea leads to penile curvature.

11) Dorsal vein of penis drains into?
a) Prostatic venous plexus
b) External iliac vein
c) Inferior epigastric vein
d) Portal vein

Answer: a) Prostatic venous plexus

Explanation: Deep dorsal vein drains into prostatic plexus, clinically important in infections and metastasis.

Chapter: Cell Biology; Topic: Meiosis; Subtopic: Stages of Meiotic Prophase I

Keyword Definitions:

• Meiosis: A specialized cell division producing haploid gametes from diploid germ cells.

• Prophase I: Longest meiotic phase with distinct substages—leptotene, zygotene, pachytene, diplotene, diakinesis.

• Leptotene: Chromosomes begin to condense into long thin threads.

• Pachytene: Homologous chromosomes fully synapse; crossing over occurs.

• Crossing Over: Exchange of genetic material during pachytene contributing to genetic diversity.

1) Lead Question – 2016
Leptotene and pachytene are stages of which phase of meiosis–
A) Prophase I
B) Metaphase I
C) Anaphase II
D) Telophase II

Answer: A) Prophase I

Explanation: Prophase I is the most complex phase of meiosis and is subdivided into leptotene, zygotene, pachytene, diplotene, and diakinesis. Leptotene marks early chromatin condensation, while pachytene involves synapsis of homologous chromosomes and crossing over. These events do not occur in metaphase I, anaphase II, or telophase II. Therefore, A is correct. Identifying these substages is essential in understanding the chromosomal behavior leading to genetic recombination and proper segregation during gametogenesis.

2) Crossing over occurs during which stage of meiosis?
A) Leptotene
B) Pachytene
C) Diakinesis
D) Metaphase I

Answer: B) Pachytene

Explanation: Pachytene is the stage in prophase I where homologous chromosomes are fully synapsed and crossing over occurs through chiasmata formation. Leptotene shows partial chromatin condensation; diakinesis involves terminalization of chiasmata; metaphase I aligns bivalents at the equator. Thus, B is the correct answer, underscoring the significance of pachytene in generating genetic variability.

3) A genetic disorder involving defective synaptonemal complex formation would most directly affect–
A) Zygotene
B) Anaphase I
C) Anaphase II
D) Telophase I

Answer: A) Zygotene

Explanation: During zygotene, homologous chromosomes pair through the synaptonemal complex. Defects in this complex prevent proper synapsis, leading to meiotic arrest or aneuploidy. Anaphase and telophase stages involve chromosome segregation and do not require synaptonemal formation. Therefore, A is correct, highlighting the essential role of zygotene in homolog pairing during meiosis.

4) Terminalization of chiasmata occurs in–
A) Diplotene
B) Zygotene
C) Pachytene
D) Leptotene

Answer: A) Diplotene

Explanation: Diplotene follows pachytene and is characterized by partial separation of homologs as chiasmata move toward the chromosome ends (terminalization). Zygotene involves synapsis; pachytene involves crossing over; leptotene shows early condensation. Thus, A is correct. Diplotene is also prolonged in oocytes, remaining arrested until ovulation, making this stage clinically significant.

5) Oocytes in a newborn female are arrested in which stage?
A) Pachytene
B) Diplotene
C) Metaphase II
D) Anaphase I

Answer: B) Diplotene

Explanation: Primary oocytes arrest in prophase I at the diplotene (dictyotene) stage until puberty. Pachytene and earlier phases are completed embryonically. Metaphase II occurs after ovulation. Thus, B is correct. Understanding this arrest is key in reproductive physiology and disorders involving oocyte maturation.

6) A patient with infertility shows failure of homologous chromosomes to separate in meiosis I. This is termed–
A) Non-disjunction
B) Aneuploidy correction
C) Synapsis
D) Terminalization

Answer: A) Non-disjunction

Explanation: Non-disjunction is the failure of homologous chromosomes to separate during anaphase I or sister chromatids in anaphase II, leading to aneuploid gametes. Synapsis and terminalization occur earlier in prophase I. Thus, A is correct. Non-disjunction underlies disorders such as Down, Edwards, and Patau syndromes.

7) Synapsis occurs during–
A) Diplotene
B) Zygotene
C) Anaphase I
D) Telophase II

Answer: B) Zygotene

Explanation: Zygotene is defined by the pairing (synapsis) of homologous chromosomes through the synaptonemal complex. Diplotene shows separation, while anaphase and telophase involve chromatid movement and nuclear reformation. Thus, B is correct, highlighting critical initial alignment of homologs in meiosis.

8) Which stage immediately follows pachytene?
A) Leptotene
B) Diplotene
C) Zygotene
D) Diakinesis

Answer: B) Diplotene

Explanation: The sequence of prophase I is leptotene → zygotene → pachytene → diplotene → diakinesis. Thus, diplotene follows pachytene. This distinguishes the progressive structural changes in chromosome morphology essential for successful meiosis. Therefore, B is correct.

9) A woman undergoing assisted reproduction has secondary oocytes arrested in–
A) Prophase I
B) Metaphase II
C) Anaphase I
D) Telophase I

Answer: B) Metaphase II

Explanation: Secondary oocytes arrest in metaphase II until fertilization. Prophase I arrest occurs in primary oocytes. Anaphase and telophase follow metaphase only after activation. Hence, B is correct. This arrest mechanism ensures proper timing of meiotic completion during fertilization.

10) Which phase shows maximum chromosomal condensation before meiosis I ends?
A) Zygotene
B) Pachytene
C) Diakinesis
D) Diplotene

Answer: C) Diakinesis

Explanation: Diakinesis marks the final stage of prophase I with maximal condensation of chromosomes, nuclear envelope breakdown, and spindle attachment preparation. Other stages show partial condensation. Thus, C is correct, highlighting the transition into metaphase I.

11) Failure of crossing over during pachytene most likely increases risk of–
A) Balanced translocation
B) Non-disjunction
C) Polyploidy
D) Terminal deletion

Answer: B) Non-disjunction

Explanation: Crossing over stabilizes homolog pairing. Absence of recombination weakens chiasmata, increasing the risk of homologs separating improperly during anaphase I, resulting in non-disjunction. Polyploidy usually arises from cytokinesis failure. Balanced translocations and deletions involve structural chromosomal changes not directly linked to absence of crossing over. Thus, B is correct.

Chapter: Physiology – Reproductive Physiology; Topic: Spermatogenesis; Subtopic: Meiotic Events in Sperm Formation

Keyword Definitions:

• Spermatogonia: Diploid male germ cells undergoing mitosis before meiosis.

• Primary Spermatocyte: Cell entering meiosis I with paired homologous chromosomes.

• Independent Assortment: Random segregation of maternal and paternal homologous chromosomes during meiosis I.

• Secondary Spermatocyte: Haploid cell after meiosis I containing separated homologs.

• Spermatid: Haploid product of meiosis II before morphological maturation.

1) Lead Question – 2016
In spermatogenesis, independent assortment of paternal and maternal chromosomes occurs during–
A) Primary to secondary spermatocyte
B) Spermatogonia to primary spermatocyte
C) Secondary spermatocyte to spermatids
D) Spermatids to spermatozoa

Answer: A) Primary to secondary spermatocyte

Explanation: Independent assortment occurs during meiosis I, specifically in anaphase I when homologous chromosomes separate randomly. In spermatogenesis, this transition corresponds to the change from primary to secondary spermatocyte. Spermatogonia undergo mitosis and therefore cannot show independent assortment. Secondary spermatocytes undergo meiosis II, which only separates sister chromatids without assortment. Spermiogenesis, the conversion of spermatids to spermatozoa, involves morphological changes rather than chromosomal segregation. Thus, the correct answer is A, representing the meiotic step responsible for generating genetic variability in male gametes.

2) Crossing over, which contributes to genetic variability, occurs during–
A) Metaphase I
B) Prophase I
C) Telophase II
D) Interphase

Answer: B) Prophase I

Explanation: Crossing over takes place during prophase I of meiosis when homologous chromosomes undergo synapsis and exchange genetic segments. This increases genetic diversity in gametes. It does not occur during metaphase I, where chromosomes simply align, nor during telophase II, which involves final chromatid separation. Interphase features DNA replication but no chromosomal recombination. In spermatogenesis, this happens within primary spermatocytes. Therefore, B is correct because prophase I is the exclusive stage where recombination occurs, playing a crucial role in creating genetic variation for transmission to future generations.

3) A 25-year-old man with infertility is found to have defective separation of homologous chromosomes during meiosis I. The first affected cell type would be–
A) Spermatogonia
B) Primary spermatocyte
C) Spermatid
D) Spermatozoa

Answer: B) Primary spermatocyte

Explanation: Nondisjunction of homologous chromosomes occurs during meiosis I, which is initiated by primary spermatocytes. Spermatogonia only undergo mitosis and cannot demonstrate meiotic errors. Spermatids are the product of meiosis II and therefore arise after the nondisjunction event, while spermatozoa represent the final differentiated state. Thus, primary spermatocytes are the earliest cells where abnormalities in homolog separation manifest. Therefore, B is the correct answer because these cells directly engage in meiosis I and demonstrate defects leading to aneuploid gametes.

4) The first haploid cells formed during spermatogenesis are–
A) Spermatogonia
B) Primary spermatocytes
C) Secondary spermatocytes
D) Sertoli cells

Answer: C) Secondary spermatocytes

Explanation: Secondary spermatocytes arise after meiosis I, where homologous chromosomes separate, producing haploid cells. Spermatogonia remain diploid and divide mitotically. Primary spermatocytes are also diploid but contain duplicated chromatids. Sertoli cells are supportive somatic cells and not germ cells. Therefore, the first haploid cells in the spermatogenic sequence are secondary spermatocytes. Hence, C is correct because these cells mark the transition from diploidy to haploidy within the meiotic process, representing the successful completion of meiosis I.

5) A 32-year-old male has abnormal sperm with defective acrosome formation. This defect most likely occurred during–
A) Meiosis I
B) Meiosis II
C) Spermiogenesis
D) Spermatogonial mitosis

Answer: C) Spermiogenesis

Explanation: Spermiogenesis transforms spermatids into mature spermatozoa and includes formation of the acrosome, condensation of the nucleus, and development of the flagellum. Meiosis I and II involve chromosomal reduction and separation but not morphological changes. Spermatogonial mitosis is strictly proliferative. Therefore, a defect in acrosome formation specifically implicates spermiogenesis. The correct answer is C because acrosome biogenesis and structural maturation occur exclusively during this phase, essential for oocyte penetration during fertilization.

6) Which cell type contains 46 chromosomes and 92 chromatids?
A) Spermatogonia
B) Primary spermatocyte
C) Secondary spermatocyte
D) Spermatid

Answer: B) Primary spermatocyte

Explanation: Primary spermatocytes arise after DNA replication, possessing 46 chromosomes with duplicated sister chromatids, totaling 92 chromatids, before entering meiosis I. Spermatogonia also contain 46 chromosomes but only 46 chromatids except during S-phase. Secondary spermatocytes and spermatids are haploid with 23 chromosomes. Thus, B is correct because primary spermatocytes uniquely hold the doubled chromatid complement, preparing for meiotic reduction while maintaining diploidy until anaphase I separation.

7) A 29-year-old male with low sperm motility most likely has a defect in–
A) Flagellar axoneme formation
B) Anaphase I separation
C) Spermatogonial mitosis
D) Crossing over

Answer: A) Flagellar axoneme formation

Explanation: Sperm motility depends on a functional flagellum, which contains a 9+2 axoneme structure powered by dynein arms. A defect here directly lowers motility. Anaphase I separation affects chromosomal segregation, not motility. Spermatogonial mitosis impacts germ cell numbers but not movement. Crossing over pertains to genetic recombination rather than motility. Therefore, A is correct because axonemal abnormalities are a primary cause of asthenozoospermia, impairing progressive sperm motility essential for fertility.

8) The immediate product of meiosis II in spermatogenesis is–
A) Spermatogonia
B) Primary spermatocyte
C) Spermatid
D) Sertoli cell

Answer: C) Spermatid

Explanation: Meiosis II separates sister chromatids, producing spermatids, which are haploid cells. Spermatogonia undergo mitosis, not meiosis. Primary spermatocytes enter meiosis I, not II. Sertoli cells are non-dividing supportive cells. Therefore, spermatids are the immediate product of meiosis II. C is correct because these cells represent the earliest stage of haploid germ cells ready to undergo spermiogenesis for final maturation into motile spermatozoa.

9) Nondisjunction of sister chromatids occurs during–
A) Meiosis I
B) Meiosis II
C) Spermiogenesis
D) Interphase

Answer: B) Meiosis II

Explanation: Sister chromatids separate during meiosis II, making nondisjunction at this stage a failure in chromatid segregation. Meiosis I separates homologous chromosomes, not sister chromatids. Spermiogenesis involves structural remodeling, not chromosomal events. Interphase includes DNA replication but no segregation. Thus, B is correct because meiosis II is the phase where chromatids are expected to separate properly, and failures lead to abnormal haploid cells with chromosomal imbalance.

10) A 24-year-old male has impaired Sertoli cell function. Which process is most affected?
A) Blood-testis barrier formation
B) Testosterone synthesis
C) LH secretion
D) Seminal vesicle contraction

Answer: A) Blood-testis barrier formation

Explanation: Sertoli cells create the blood-testis barrier, support germ cells, produce inhibin, and regulate spermatogenesis. They do not synthesize testosterone—that is the role of Leydig cells. LH secretion is regulated by the hypothalamus and pituitary. Seminal vesicle contraction is influenced by the sympathetic nervous system. Therefore, A is correct because Sertoli cells uniquely contribute structural and functional support needed for germ cell protection and maturation.

11) The stage of spermatogenesis involving transformation of haploid cells into mature spermatozoa is–
A) Meiosis I
B) Meiosis II
C) Spermiogenesis
D) Spermatogonial proliferation

Answer: C) Spermiogenesis

Explanation: Spermiogenesis is the process in which spermatids undergo morphological changes including acrosome formation, nuclear condensation, flagellum development, and shedding of excess cytoplasm. Meiosis I and II involve chromosomal reduction and division but not morphologic maturation. Spermatogonial proliferation increases germ cell number but does not contribute to final differentiation. Thus, C is correct because spermiogenesis specifically converts haploid spermatids into fully formed spermatozoa necessary for fertilization.

Chapter: Reproductive Physiology; Topic: Early Embryonic Development; Subtopic: Transport of Zygote and Role of Zona Pellucida

KEYWORD DEFINITIONS

• Zygote – Fertilized ovum formed after fusion of sperm and oocyte

• Zona pellucida – Glycoprotein layer surrounding early embryo, prevents implantation during transport

• Morula – 16–32 cell stage developing before blastocyst

• Fallopian tube transport – Movement of embryo toward uterus over several days

• Implantation – Embedding of blastocyst into endometrium after shedding zona pellucida

Lead Question – 2016

1. Zygote with zona pellucida reaches uterine cavity by:

A) 2 days

B) 4 days

C) 5 days

D) 6 days

Explanation:

After fertilization in the ampulla of the fallopian tube, the zygote divides to form a morula and moves toward the uterus assisted by ciliary action and smooth muscle contractions. The embryo covered by zona pellucida reaches the uterine cavity around day 4 after fertilization. The zona pellucida prevents premature implantation during tubal transit. Implantation begins only after zona shedding, typically around day 6. Therefore, the correct answer is 4 days. This timing is essential for normal embryonic development.

2. Zona pellucida disappears by which stage?

A) Zygote

B) Morula

C) Early blastocyst

D) Late blastocyst

Explanation:

Zona pellucida is shed during early blastocyst formation to allow implantation into the endometrium. At the morula stage, the embryo still remains surrounded by zona. Zygote also retains zona. Therefore, the correct answer is Early blastocyst. This step, called “hatching,” is essential for implantation readiness.

3. Fertilization usually occurs in:

A) Uterine cavity

B) Cervix

C) Ampulla of fallopian tube

D) Isthmus of fallopian tube

Explanation:

The ampulla of the fallopian tube provides the optimal environment for fertilization due to its wide lumen and presence of cilia. The uterus and cervix are not suitable for fertilization, while the isthmus is too narrow. Thus, the correct answer is Ampulla of fallopian tube. Post-fertilization, the zygote begins cleavage and moves toward the uterus.

4. A patient with damaged fallopian tube cilia is most likely to experience:

A) Early uterine implantation

B) Delayed embryo transport

C) Increased fertility

D) None

Explanation:

Ciliary movement is crucial for proper transport of the zygote. Damage causes delayed transport, increasing the risk of ectopic pregnancy. Early uterine implantation does not occur with delayed movement. Therefore, the correct answer is Delayed embryo transport. This highlights the importance of tubal health in fertility.

5. Implantation typically occurs on which day post-fertilization?

A) Day 2

B) Day 4

C) Day 6–7

D) Day 12

Explanation:

Implantation begins when the blastocyst attaches to the endometrium, typically around day 6–7 after fertilization. Earlier days represent cleavage stages, while day 12 corresponds to deeper placental embedding. Therefore, the correct answer is Day 6–7. Successful implantation requires synchronized endometrial receptivity.

6. Morula typically forms on which day after fertilization?

A) Day 1

B) Day 2

C) Day 3

D) Day 6

Explanation:

The morula forms around day 3 as the zygote undergoes multiple cleavage divisions. It remains surrounded by the zona pellucida until the blastocyst stage. Day 6 corresponds to implantation. Thus, the correct answer is Day 3. The compacted morula then enters the uterine cavity by day 4.

7. Failure of zona hatching causes:

A) Ectopic pregnancy

B) Infertility due to implantation failure

C) Multiple pregnancy

D) Early abortion

Explanation:

If the zona pellucida does not shed, the blastocyst cannot implant into the endometrium, resulting in implantation failure and infertility. Ectopic pregnancy occurs when premature implantation happens in the tube. Therefore, the correct answer is Infertility due to implantation failure. Assisted reproductive techniques sometimes assist hatching.

8. Which hormone prepares endometrium for implantation?

A) FSH

B) LH

C) Estrogen

D) Progesterone

Explanation:

Progesterone transforms the endometrium from proliferative to secretory phase, making it receptive to blastocyst implantation. Estrogen induces proliferation, but progesterone prepares for implantation. FSH and LH regulate ovarian function. Therefore, the correct answer is Progesterone. Adequate progesterone is essential for pregnancy maintenance.

9. A woman with luteal phase defect may experience:

A) Late fertilization

B) Implantation failure

C) Multiple ovulation

D) Increased FSH levels

Explanation:

Luteal phase defect causes insufficient progesterone production, leading to inadequate endometrial receptivity and implantation failure. Fertilization and ovulation remain normal. Thus, the correct answer is Implantation failure. This may present clinically as recurrent early pregnancy loss.

10. Blastocyst contains which two major structures?

A) Trophoblast & inner cell mass

B) Zona pellucida & morula

C) Uterus & cervix

D) Epiblast & hypoblast only

Explanation:

The blastocyst consists of trophoblast cells forming the future placenta and the inner cell mass forming the embryo. Zona exists earlier, not at this stage. Epiblast and hypoblast form later during bilaminar development. Therefore, the correct answer is Trophoblast & inner cell mass. This stage is critical for implantation.

11. Implantation normally occurs at which region of the uterus?

A) Internal os

B) Lower uterine segment

C) Upper posterior wall

D) Cervical canal

Explanation:

Implantation most commonly occurs on the upper posterior uterine wall where blood supply and endometrial thickness are optimal. Implantation at internal os or lower segment is abnormal and leads to placenta previa. Cervical implantation is rare and dangerous. Thus, the correct answer is Upper posterior wall. Proper localization ensures healthy placental development. 

Chapter: Anatomy; Topic: Male Reproductive System; Subtopic: Structures of Prostatic Urethra

Keyword Definitions:
• Seminal colliculus: Elevation on posterior wall of prostatic urethra where ejaculatory ducts open.
• Prostatic urethra: Portion of urethra passing through prostate containing urethral crest.
• Ejaculatory ducts: Ducts opening into prostatic urethra formed by union of vas deferens and seminal vesicle duct.
• Prostate gland: Gland surrounding prostatic urethra producing seminal fluid.
• Urethral crest: Ridge containing seminal colliculus in prostatic urethra.
• Prostatic sinuses: Lateral depressions where prostatic ducts open into urethra.

Lead Question - 2015
Seminal colliculus is present in?
a) Testis
b) Prostate
c) Urethra
d) Scrotum

Explanation (Answer: c) Urethra)
The seminal colliculus is a prominent elevation located in the prostatic urethra along the urethral crest. It is the site where the ejaculatory ducts open, marking a key anatomical landmark during endoscopic urological procedures. Though situated within the prostate, it specifically belongs to the urethra. It contains the prostatic utricle opening as well and plays an essential role in the male reproductive tract.

1. Ejaculatory ducts open into which structure?
a) Membranous urethra
b) Prostatic urethra
c) Spongy urethra
d) Bladder neck

Explanation (Answer: b) Prostatic urethra)
The ejaculatory ducts open into the prostatic urethra at the seminal colliculus. This region also contains prostatic utricle opening. The prostatic urethra serves as a pathway for semen to join urinary flow. Any obstruction here can affect ejaculation or cause retention. Its anatomy is essential during TURP procedures and cystoscopies.

2. Prostatic utricle is associated with:
a) Seminal colliculus
b) Bladder trigone
c) Epididymis
d) Seminal vesicle

Explanation (Answer: a) Seminal colliculus)
The prostatic utricle is a small pouch opening into the seminal colliculus. It represents a remnant of the Müllerian duct. Though small, it may become enlarged in persistent Müllerian duct syndrome. Its opening lies between entrances of ejaculatory ducts and is visible during cystoscopy as part of urethral crest structures.

3. Which part of urethra passes through prostate?
a) Membranous urethra
b) Prostatic urethra
c) Spongy urethra
d) Penile urethra

Explanation (Answer: b) Prostatic urethra)
The prostatic urethra runs through the prostate gland and contains key landmarks like the urethral crest, seminal colliculus, and prostatic sinuses. It receives ejaculatory ducts and prostatic secretions. If enlarged prostate compresses this region, urinary obstruction and retention may occur, commonly seen in elderly males with BPH.

4. Enlargement of which gland leads to compression of prostatic urethra?
a) Seminal vesicle
b) Prostate
c) Bulbourethral gland
d) Parotid

Explanation (Answer: b) Prostate)
The prostatic urethra is enclosed by the prostate. In benign prostatic hyperplasia (BPH), enlargement of prostate compresses urethra causing urinary obstruction, hesitancy, and weak stream. Since seminal colliculus lies here, it may be distorted during adenoma expansion. TURP surgery targets this region for symptomatic relief.

5. Which structure is NOT part of prostatic urethra?
a) Prostatic sinus
b) Seminal colliculus
c) Bulbourethral duct opening
d) Prostatic utricle

Explanation (Answer: c) Bulbourethral duct opening)
Bulbourethral ducts open into the spongy urethra, not into the prostatic urethra. The prostatic urethra contains prostatic sinuses, seminal colliculus, and prostatic utricle. These structures are important in urological evaluation and drainage of prostatic secretions into the urethral lumen.

6. Seminal colliculus is located on:
a) Anterior urethral wall
b) Posterior urethral wall
c) Lateral urethral wall
d) Floor of urethra

Explanation (Answer: b) Posterior urethral wall)
The seminal colliculus forms a raised elevation on the posterior wall of the prostatic urethra, part of the urethral crest. This location is essential for understanding cystoscopic landmarks. It also receives openings of ejaculatory ducts—one on each side of prostatic utricle, aiding semen entry into urethral passage.

7. Pain during ejaculation may result from obstruction at:
a) Membranous urethra
b) Seminal colliculus
c) External urethral meatus
d) Perineal urethra

Explanation (Answer: b) Seminal colliculus)
Obstruction or inflammation around the seminal colliculus may impede ejaculatory duct entry into urethra, causing painful ejaculation. Chronic prostatitis may lead to swelling of this region. Blockage affects emission pathway leading to discomfort. Cystoscopy may reveal mucosal elevation or stenosis around this anatomical landmark.

8. Prostatic urethra receives prostatic ducts into:
a) Seminal colliculus
b) Prostatic sinuses
c) Prostatic utricle
d) Ejaculatory ducts

Explanation (Answer: b) Prostatic sinuses)
Prostatic ducts drain into prostatic sinuses, which are depressions on either side of the urethral crest in the prostatic urethra. Seminal colliculus mainly receives ejaculatory ducts and prostatic utricle opening. Understanding duct openings aids in diagnosing reflux, infections, or obstruction-related disorders in male reproductive anatomy.

9. Seminal colliculus is also referred to as:
a) Adam’s ridge
b) Verumontanum
c) Prostatic fossa
d) Seminal pit

Explanation (Answer: b) Verumontanum)
Verumontanum is the alternate name for the seminal colliculus. It is an important cystoscopic landmark inside the prostatic urethra. The ejaculatory ducts open here, appearing as paired openings. It helps clinicians orient themselves during urological procedures such as TURP, preventing inadvertent damage to vital reproductive structures.

10. A boy with midline cystic swelling in prostatic urethra likely has dilation of:
a) Ejaculatory ducts
b) Prostatic utricle
c) Urethral glands
d) Bulbourethral duct

Explanation (Answer: b) Prostatic utricle)
A dilated prostatic utricle appears as a midline cystic structure during evaluation of prostatic urethra. It opens at the seminal colliculus. Congenital enlargement can cause urinary tract symptoms or infection. Utricular cysts are associated with hypospadias and persistent Müllerian duct syndrome, requiring follow-up imaging and possible intervention.

Chapter: Embryology; Topic: Cell Division; Subtopic: Meiotic Prophase I – Stages and Significance

Key Definitions:

• Meiosis: A specialized form of cell division that reduces the chromosome number by half, producing haploid gametes.

• Prophase I: The first and longest stage of meiosis I, during which homologous chromosomes pair and exchange genetic material through crossing over.

• Synapsis: The pairing of homologous chromosomes during zygotene stage of prophase I.

• Crossing over: Exchange of genetic material between non-sister chromatids of homologous chromosomes during pachytene, leading to genetic variation.

Lead Question (NEET PG 2015):

1. Which is not a stage of prophase?

a) Diakinesis

b) Leptotene

c) Zygotene

d) Arachytene

Answer: d) Arachytene

Explanation: Prophase I of meiosis is divided into five distinct stages — leptotene, zygotene, pachytene, diplotene, and diakinesis. Each stage has unique events: pairing of homologous chromosomes, synapsis, and crossing over occur sequentially. The term “Arachytene” is incorrect and does not exist as a recognized substage of prophase I. During this prolonged phase, the genetic material undergoes condensation, recombination, and preparation for segregation. This stage is crucial for ensuring genetic variability and accurate chromosome segregation during gametogenesis.

Guessed Questions (Related to Meiotic Prophase I and Cell Division):

2. Crossing over occurs during which stage of prophase I?

a) Leptotene

b) Zygotene

c) Pachytene

d) Diplotene

Answer: c) Pachytene

Explanation: Crossing over occurs during pachytene, where homologous chromosomes exchange genetic material between non-sister chromatids at chiasmata. This process contributes to genetic diversity among gametes and is mediated by the enzyme recombinase.

3. Synapsis or pairing of homologous chromosomes occurs during:

a) Leptotene

b) Zygotene

c) Diplotene

d) Metaphase

Answer: b) Zygotene

Explanation: During zygotene, homologous chromosomes begin to pair along their lengths through a protein structure called the synaptonemal complex. This pairing is essential for crossing over in the next stage, pachytene.

4. Clinical: Nondisjunction leading to Down syndrome usually occurs during:

a) Prophase I

b) Metaphase I

c) Anaphase I

d) Telophase I

Answer: c) Anaphase I

Explanation: Nondisjunction, the failure of homologous chromosomes to separate properly, occurs during anaphase I of meiosis. This results in aneuploidy, such as trisomy 21 (Down syndrome), when a gamete with an extra chromosome fuses during fertilization.

5. Diplotene stage of prophase I is characterized by:

a) Disappearance of chiasmata

b) Terminalization of chiasmata

c) Separation of homologous chromosomes except at chiasmata

d) Formation of spindle fibers

Answer: c) Separation of homologous chromosomes except at chiasmata

Explanation: In the diplotene stage, homologous chromosomes begin to separate but remain attached at chiasmata — the sites of crossing over. This stage may be prolonged, especially in oocytes, where it can last until puberty.

6. Clinical: Arrest of oocytes in females occurs at which stage of meiosis?

a) Pachytene

b) Diplotene

c) Diakinesis

d) Anaphase I

Answer: b) Diplotene

Explanation: Primary oocytes in females remain arrested in diplotene stage of prophase I from fetal life until puberty. Meiosis resumes during each menstrual cycle after hormonal stimulation by LH.

7. The disappearance of the nuclear membrane and nucleolus occurs during which substage of prophase I?

a) Pachytene

b) Diplotene

c) Diakinesis

d) Leptotene

Answer: c) Diakinesis

Explanation: Diakinesis is the final stage of prophase I, marked by maximal chromosome condensation and disappearance of the nuclear membrane and nucleolus. The spindle apparatus begins to form, preparing for metaphase I alignment.

8. Clinical: A woman’s oocytes remaining arrested for decades may accumulate DNA damage. This increases risk of:

a) Monosomy

b) Polyploidy

c) Aneuploidy

d) Triploidy

Answer: c) Aneuploidy

Explanation: Oocytes arrested in diplotene for prolonged periods are prone to errors during chromosome segregation when meiosis resumes, leading to aneuploidy (e.g., trisomy 21, 18, 13). This risk increases with maternal age.

9. The synaptonemal complex first appears during:

a) Leptotene

b) Zygotene

c) Pachytene

d) Diakinesis

Answer: b) Zygotene

Explanation: The synaptonemal complex, a tripartite protein structure, forms during zygotene and facilitates homologous chromosome pairing and recombination during pachytene.

10. Clinical: A 40-year-old woman gives birth to a baby with trisomy 21. The error most likely occurred during:

a) Maternal meiosis I

b) Maternal meiosis II

c) Spermatogenesis

d) Zygotic mitosis

Answer: a) Maternal meiosis I

Explanation: In most cases of Down syndrome, nondisjunction occurs during maternal meiosis I due to aging oocytes and improper homologous chromosome separation during prophase I and anaphase I.

11. During which meiotic stage does chromosomal recombination (genetic exchange) take place?

a) Leptotene

b) Zygotene

c) Pachytene

d) Diplotene

Answer: c) Pachytene

Explanation: Chromosomal recombination occurs during pachytene as homologous chromosomes exchange segments of genetic material at chiasmata. This ensures genetic diversity among gametes, a fundamental outcome of meiosis.

Topic: Reproductive System; Subtopic: Spermatogenesis – Process and Regulation

Key Definitions:

• Spermatogenesis: The process of sperm formation from spermatogonia occurring in the seminiferous tubules of the testes.

• Spermatogonia: Diploid stem cells located at the periphery of seminiferous tubules that divide mitotically and initiate spermatogenesis.

• Puberty: The stage of life when reproductive capability begins, characterized by activation of the hypothalamic-pituitary-gonadal axis.

• Sertoli cells: Supporting cells in the seminiferous tubules that nourish developing sperm and form the blood-testis barrier.

Lead Question (NEET PG 2015):

1. Spermatogenesis begins at:

a) Birth

b) 5 years

c) Puberty

d) 18 years

Answer: c) Puberty

Explanation: Spermatogenesis begins at puberty under the influence of gonadotropins (LH and FSH). LH stimulates Leydig cells to secrete testosterone, while FSH acts on Sertoli cells to support sperm maturation. Before puberty, spermatogonia remain dormant in the seminiferous tubules. With increased GnRH secretion at puberty, hormonal stimulation triggers the differentiation of spermatogonia into primary spermatocytes, initiating sperm formation. The process continues throughout life, producing millions of sperm daily. It takes approximately 64–74 days for a spermatogonium to mature into a spermatozoon.

Guessed Questions (Related to Spermatogenesis):

2. The process of spermatogenesis occurs in which structure?

a) Epididymis

b) Seminiferous tubules

c) Vas deferens

d) Rete testis

Answer: b) Seminiferous tubules

Explanation: Spermatogenesis takes place in the seminiferous tubules of the testes. The walls of these tubules contain spermatogenic cells in various stages of development supported by Sertoli cells. Mature sperm are released into the lumen and transported to the epididymis for storage and motility development.

3. Which hormone directly stimulates spermatogenesis?

a) LH

b) FSH

c) Prolactin

d) Inhibin

Answer: b) FSH

Explanation: FSH (Follicle Stimulating Hormone) acts on Sertoli cells, promoting spermatogenesis and the secretion of androgen-binding protein (ABP), which maintains high local testosterone levels essential for sperm maturation. LH acts indirectly by stimulating testosterone production from Leydig cells.

4. Clinical: A teenage boy with delayed puberty and small testes likely has deficiency of which hormone?

a) Growth hormone

b) Gonadotropin-releasing hormone (GnRH)

c) Aldosterone

d) Oxytocin

Answer: b) Gonadotropin-releasing hormone (GnRH)

Explanation: GnRH from the hypothalamus stimulates the anterior pituitary to release FSH and LH. Deficiency of GnRH delays puberty and spermatogenesis, leading to hypogonadotropic hypogonadism, as seen in Kallmann syndrome.

5. The process of spermiogenesis refers to:

a) Formation of spermatogonia

b) Conversion of spermatids into mature spermatozoa

c) Formation of primary spermatocytes

d) Release of sperm into seminiferous lumen

Answer: b) Conversion of spermatids into mature spermatozoa

Explanation: Spermiogenesis is the final stage of spermatogenesis in which non-motile, round spermatids differentiate into motile spermatozoa. This involves nuclear condensation, acrosome formation, flagellum development, and cytoplasmic reduction.

6. Clinical: A man with low sperm count and normal testosterone levels most likely has a defect in:

a) Leydig cells

b) Sertoli cells

c) Adrenal cortex

d) Hypothalamus

Answer: b) Sertoli cells

Explanation: Sertoli cells are responsible for nourishing developing sperm, maintaining the blood-testis barrier, and secreting inhibin and ABP. Damage or dysfunction of these cells results in oligospermia despite normal testosterone levels from functional Leydig cells.

7. Which of the following cells undergo meiosis I during spermatogenesis?

a) Spermatogonia

b) Primary spermatocytes

c) Secondary spermatocytes

d) Spermatids

Answer: b) Primary spermatocytes

Explanation: Primary spermatocytes undergo meiosis I to form haploid secondary spermatocytes. These then undergo meiosis II to form spermatids, which eventually mature into spermatozoa during spermiogenesis.

8. Clinical: After vasectomy, which of the following remains unaffected?

a) Spermatogenesis

b) Ejaculation of sperm

c) Fertility

d) Sperm transport to urethra

Answer: a) Spermatogenesis

Explanation: Spermatogenesis continues normally after vasectomy because testicular function and hormone secretion remain intact. However, sperm cannot reach the urethra due to vas deferens ligation, resulting in sterility.

9. Which hormone inhibits FSH secretion to regulate spermatogenesis?

a) Inhibin

b) Testosterone

c) Estrogen

d) GnRH

Answer: a) Inhibin

Explanation: Inhibin, secreted by Sertoli cells, specifically suppresses FSH secretion from the anterior pituitary. This provides a feedback mechanism to regulate sperm production and maintain testicular homeostasis.

10. Clinical: A 22-year-old male presents with infertility and testicular biopsy showing absence of germ cells but normal Leydig cells. This condition is known as:

a) Sertoli cell-only syndrome

b) Klinefelter syndrome

c) Cryptorchidism

d) Varicocele

Answer: a) Sertoli cell-only syndrome

Explanation: Sertoli cell-only syndrome (Del Castillo syndrome) is characterized by complete absence of germ cells in seminiferous tubules with normal Sertoli and Leydig cells. Spermatogenesis fails, leading to azoospermia and infertility.

11. The approximate duration of spermatogenesis from spermatogonium to spermatozoon is:

a) 24 hours

b) 21 days

c) 64 days

d) 90 days

Answer: c) 64 days

Explanation: The entire process of spermatogenesis takes approximately 64 to 74 days. This includes mitotic divisions of spermatogonia, meiotic divisions of spermatocytes, and spermiogenesis. After this, spermatozoa spend another 10–14 days in the epididymis to acquire motility and fertilizing capacity.

Chapter: Anatomy; Topic: Female Reproductive System; Subtopic: Vagina – Histology and Structural Features

Key Definitions:

• Vagina: A fibromuscular canal extending from the cervix of the uterus to the external vaginal orifice, serving as a part of the birth canal and copulatory organ.

• Lining epithelium: The epithelial tissue that covers the inner surface of an organ; in the vagina, it provides protection against friction and infection.

• Stratified squamous non-keratinized epithelium: Multi-layered epithelium that protects against mechanical stress and maintains moisture; the type lining the vagina.

• Glycogen-rich cells: Vaginal epithelial cells contain glycogen, metabolized by lactobacilli to produce lactic acid, maintaining acidic pH (≈4.5).

Lead Question (NEET PG 2015):

1. Lining epithelium of vagina is:

a) Squamous epithelium

b) Columnar epithelium

c) Transitional epithelium

d) Secretory epithelium

Answer: a) Squamous epithelium

Explanation: The vagina is lined by stratified squamous non-keratinized epithelium. This multilayered epithelium provides mechanical protection and resists friction during intercourse and childbirth. It contains glycogen-rich cells that serve as substrates for vaginal lactobacilli, which maintain an acidic environment (pH 4–4.5), preventing infection. The lamina propria beneath contains elastic fibers and rich vascularity, while the muscular layer provides strength and flexibility. There are no glands in the vaginal wall; lubrication is supplied by cervical and vestibular secretions.

Guessed Questions (Related to Vaginal and Female Reproductive Histology):

2. The vaginal epithelium is derived embryologically from:

a) Müllerian duct

b) Urogenital sinus

c) Cloacal membrane

d) Wolffian duct

Answer: b) Urogenital sinus

Explanation: The lower part of the vagina develops from the urogenital sinus (endodermal origin), while the upper part originates from the Müllerian ducts (mesodermal origin). The junction between these two parts forms the hymen. This dual embryologic origin explains certain congenital anomalies such as vaginal atresia and septation.

3. The vaginal pH is maintained acidic due to the presence of:

a) Cervical mucus

b) Glycogen metabolism by lactobacilli

c) Estrogen secretion

d) Progesterone dominance

Answer: b) Glycogen metabolism by lactobacilli

Explanation: Vaginal epithelial cells store glycogen under the influence of estrogen. Lactobacilli metabolize this glycogen into lactic acid, maintaining an acidic pH (~4.5), which prevents overgrowth of pathogenic organisms. Reduced estrogen levels (as in menopause) increase pH, predisposing to infections.

4. The vagina lacks which of the following structural components?

a) Muscular layer

b) Mucous glands

c) Lamina propria

d) Adventitia

Answer: b) Mucous glands

Explanation: The vaginal mucosa does not contain glands. Its lubrication is derived from cervical secretions and Bartholin’s (greater vestibular) glands. The absence of intrinsic glands is compensated by the rich vascular network and transudation from the mucosa.

5. Clinical: In postmenopausal women, the vaginal epithelium becomes:

a) Thinner and less glycogenated

b) Thickened and keratinized

c) Columnar and secretory

d) Transitional in type

Answer: a) Thinner and less glycogenated

Explanation: After menopause, decreased estrogen leads to atrophy of the vaginal epithelium. It becomes thin, pale, and loses glycogen content, predisposing to dryness, infection, and dyspareunia (painful intercourse). This condition is termed atrophic vaginitis.

6. The upper one-third of the vagina is derived from:

a) Müllerian ducts

b) Urogenital sinus

c) Cloacal membrane

d) Wolffian duct

Answer: a) Müllerian ducts

Explanation: The upper one-third of the vagina arises from the fused Müllerian ducts, which also give rise to the uterus and fallopian tubes. The lower two-thirds come from the urogenital sinus. This junction is the embryological site of hymen formation.

7. Clinical: A patient presents with recurrent vaginal infections after menopause. Which factor contributes most to this?

a) Decrease in estrogen and loss of vaginal acidity

b) Excessive progesterone

c) Cervical stenosis

d) Overgrowth of lactobacilli

Answer: a) Decrease in estrogen and loss of vaginal acidity

Explanation: Estrogen deficiency causes thinning of the vaginal mucosa and reduces glycogen levels. This decreases lactic acid production by lactobacilli, raising vaginal pH and allowing pathogenic bacteria to proliferate, resulting in infections.

8. The epithelial type lining the cervix differs from that of the vagina as:

a) Cervix has columnar epithelium

b) Cervix has keratinized squamous epithelium

c) Cervix is lined by transitional epithelium

d) Both have the same type

Answer: a) Cervix has columnar epithelium

Explanation: The vaginal portion of the cervix (ectocervix) is covered by stratified squamous non-keratinized epithelium, continuous with the vagina, whereas the endocervical canal is lined by simple columnar epithelium that secretes mucus. The junction between them is the squamocolumnar junction (transformation zone).

9. Clinical: A biopsy from the vaginal wall of a neonate shows columnar epithelium. This finding suggests:

a) Müllerian duct anomaly

b) Persistent urogenital sinus lining

c) Early neoplastic change

d) Vitamin A deficiency

Answer: b) Persistent urogenital sinus lining

Explanation: Normally, the vaginal lining transitions from columnar to squamous epithelium during fetal development. Persistence of columnar cells indicates incomplete replacement of urogenital sinus-derived epithelium, which may cause abnormal mucus secretion or predispose to vaginal adenosis.

10. The lamina propria of the vagina contains which of the following features?

a) Dense elastic fibers and rich venous plexus

b) Cartilage plates

c) Serous glands

d) Skeletal muscle bundles

Answer: a) Dense elastic fibers and rich venous plexus

Explanation: The lamina propria of the vaginal wall is rich in elastic fibers and blood vessels, which facilitate distensibility during intercourse and childbirth. The venous plexus also contributes to the lubrication of the mucosal surface through plasma transudation.

11. Clinical: During Pap smear, the cells collected from the vaginal portion of the cervix are:

a) Stratified squamous epithelial cells

b) Simple columnar cells

c) Transitional epithelial cells

d) Cuboidal epithelial cells

Answer: a) Stratified squamous epithelial cells

Explanation: The vaginal portion of the cervix (ectocervix) is lined by stratified squamous non-keratinized epithelium, similar to the vagina. Pap smears analyze these cells for cytological abnormalities like dysplasia or carcinoma in situ, especially at the transformation zone where squamous and columnar epithelia meet.

Chapter: Anatomy; Topic: Female Reproductive System; Subtopic: Fallopian Tubes – Structure, Development, and Function

Key Definitions:

• Fallopian tube (uterine tube): A paired tubular structure extending from the uterus to the ovary, responsible for oocyte transport and fertilization.

• Müllerian ducts: Paired embryonic ducts that develop into the female reproductive tract, including fallopian tubes, uterus, and upper vagina.

• Isthmus: The narrow medial part of the fallopian tube that joins the uterus.

• Epithelium of fallopian tube: The tube is lined by ciliated columnar epithelium, not cuboidal, which helps propel the ovum toward the uterus.

Lead Question (NEET PG 2015):

1. True about fallopian tubes are all except:

a) Lined by cuboidal epithelium

b) Isthmus is the narrower part of the tube that links to the uterus

c) Tubal ostium is the point where the tubal canal meets the peritoneal cavity

d) Müllerian ducts develop in females into the Fallopian tubes

Answer: a) Lined by cuboidal epithelium

Explanation: The fallopian tube is lined by a ciliated columnar epithelium, not cuboidal. These cilia help in the transport of the ovum from the ovary toward the uterus. The tube consists of four parts: infundibulum, ampulla, isthmus, and intramural (uterine) part. The isthmus is narrow and connects the ampulla to the uterus, while the tubal ostium opens into the peritoneal cavity near the ovary. The tubes develop from the Müllerian ducts in the embryo. Fertilization most commonly occurs in the ampulla due to its wide lumen and mucosal folds.

Guessed Questions (Related to Fallopian Tubes):

2. Fertilization of the ovum usually occurs in which part of the fallopian tube?

a) Infundibulum

b) Isthmus

c) Ampulla

d) Uterine part

Answer: c) Ampulla

Explanation: The ampulla is the widest segment of the fallopian tube with extensive mucosal folds, providing an ideal site for sperm-ovum interaction. Fertilization occurs here, and the zygote is then transported toward the uterus for implantation, aided by ciliary movement and muscular contractions.

3. The fallopian tubes are derived embryologically from:

a) Wolffian ducts

b) Müllerian ducts

c) Urogenital sinus

d) Cloacal membrane

Answer: b) Müllerian ducts

Explanation: The Müllerian (paramesonephric) ducts form the fallopian tubes, uterus, and upper portion of the vagina in females. In males, these ducts regress under the influence of Müllerian inhibiting factor (MIF) produced by Sertoli cells.

4. Which of the following statements about the fallopian tube is correct?

a) Isthmus is the widest part

b) Lumen is straight without folds

c) Infundibulum has fimbriae to catch the ovum

d) Uterine part opens into the peritoneal cavity

Answer: c) Infundibulum has fimbriae to catch the ovum

Explanation: The infundibulum is funnel-shaped and bears fimbriae that sweep over the ovary to capture the ovulated ovum and direct it into the tubal lumen. The fimbriae play a crucial role in successful fertilization and pregnancy.

5. Clinical: The most common site of ectopic pregnancy is:

a) Ovary

b) Ampulla of fallopian tube

c) Isthmus

d) Cervix

Answer: b) Ampulla of fallopian tube

Explanation: The ampulla of the fallopian tube is the most common site for ectopic pregnancy (about 70%). Implantation in this site can cause tubal rupture and intraperitoneal hemorrhage, leading to acute abdomen and shock if untreated.

6. The epithelial lining of the fallopian tube mainly consists of:

a) Ciliated columnar cells

b) Simple squamous cells

c) Cuboidal cells

d) Stratified columnar cells

Answer: a) Ciliated columnar cells

Explanation: The mucosa of the fallopian tube is lined by ciliated columnar epithelial cells. The cilia beat toward the uterus, helping in the propulsion of the ovum and zygote. Secretory (peg) cells are also present to provide nourishment for the ovum.

7. The peritoneal opening of the fallopian tube is termed as:

a) Internal os

b) External os

c) Tubal ostium

d) Infundibular fold

Answer: c) Tubal ostium

Explanation: The tubal ostium (abdominal ostium) is the opening of the fallopian tube into the peritoneal cavity through the infundibulum. It provides a direct connection between the peritoneal cavity and the uterine lumen, which is important in ovum transport.

8. Clinical: A woman with pelvic inflammatory disease (PID) develops infertility due to blockage of which structure?

a) Isthmus of fallopian tube

b) Cervical canal

c) Internal os

d) Uterine cavity

Answer: a) Isthmus of fallopian tube

Explanation: Pelvic inflammatory disease leads to fibrosis and scarring of the fallopian tubes, particularly the isthmus. This causes blockage and prevents the passage of the ovum to the uterus, resulting in infertility or ectopic pregnancy.

9. The narrowest part of the fallopian tube is:

a) Ampulla

b) Infundibulum

c) Isthmus

d) Uterine part

Answer: d) Uterine part

Explanation: The uterine part (interstitial segment) is the narrowest portion of the fallopian tube, lying within the uterine wall. It opens into the uterine cavity through the uterine ostium and is clinically significant for embryo implantation and tubal block assessments.

10. Clinical: A surgeon performing tubal ligation usually clamps the tube at which part?

a) Infundibulum

b) Isthmus

c) Ampulla

d) Uterine part

Answer: b) Isthmus

Explanation: The isthmus is chosen for tubal ligation because it is narrow, straight, and easily accessible. Occluding this segment effectively prevents the meeting of sperm and ovum while minimizing surgical complications.

11. Clinical: During laparoscopic examination, fimbriae are not visualized. This indicates a defect in which part of the fallopian tube?

a) Ampulla

b) Isthmus

c) Infundibulum

d) Uterine part

Answer: c) Infundibulum

Explanation: The fimbriae are finger-like projections of the infundibulum that capture the ovum after ovulation. Their absence or damage can lead to infertility by preventing ovum entry into the fallopian tube. Such defects are often secondary to pelvic infections or endometriosis.

Chapter: Pelvis and Perineum; Topic: Perineum; Subtopic: Superficial Perineal Pouch

Keyword Definitions:

• Perineum: The diamond-shaped area between the thighs, below the pelvic diaphragm, containing urogenital and anal triangles.

• Superficial Perineal Space: A compartment of the urogenital triangle located between the perineal membrane and Colles’ fascia.

• Ischiocavernosus Muscle: A muscle that helps maintain erection by compressing the crus of the penis or clitoris.

• Deep Transverse Perinei Muscle: A muscle present in the deep perineal pouch that helps support the pelvic floor.

• Bulbourethral Glands: Small glands in the deep perineal pouch secreting pre-ejaculate fluid for lubrication.

Lead Question (2015): Superficial perineal space contains?

a) Sphincter urethrae muscle
b) Ischiocavernosus muscle
c) Deep transverse perinei muscle
d) Bulbourethral gland

Explanation: The superficial perineal space lies between Colles’ fascia and the perineal membrane. It contains the ischiocavernosus, bulbospongiosus, and superficial transverse perinei muscles, as well as the roots of the penis or clitoris and branches of the pudendal vessels and nerves. The deep transverse perinei and bulbourethral glands are in the deep pouch. Answer: (b)

1. Which structure forms the superior boundary of the superficial perineal pouch?
a) Colles’ fascia
b) Perineal membrane
c) Deep fascia of thigh
d) Scarpa’s fascia

The perineal membrane (inferior fascia of the urogenital diaphragm) forms the superior boundary of the superficial perineal pouch. The inferior boundary is Colles’ fascia. This anatomical arrangement encloses muscles and erectile tissues of the urogenital triangle. Answer: (b)

2. The superficial transverse perinei muscle assists in:
a) Ejaculation
b) Supporting perineal body
c) Sphincter control of urethra
d) Defecation

The superficial transverse perinei muscle helps stabilize the perineal body, a fibromuscular node providing attachment to perineal muscles. It plays a supportive role in maintaining pelvic organ integrity during contraction and childbirth. Answer: (b)

3. Which structure lies in the deep perineal pouch?
a) Bulbospongiosus muscle
b) Bulbourethral glands
c) Ischiocavernosus muscle
d) Perineal branches of pudendal nerve

The bulbourethral glands (Cowper’s glands) are located in the deep perineal pouch. They secrete mucus to lubricate the urethra before ejaculation. Their ducts open into the spongy urethra, distinguishing them from structures in the superficial pouch. Answer: (b)

4. Which of the following structures passes through both superficial and deep perineal spaces?
a) Vas deferens
b) Urethra
c) Testicular artery
d) Internal pudendal vein

The urethra passes through both deep and superficial perineal spaces. The membranous part lies in the deep pouch and the spongy part in the superficial pouch. It is supported by the sphincter urethrae and bulbospongiosus muscles. Answer: (b)

5. A tear in the spongy urethra can cause urine to extravasate into:
a) Pelvic cavity
b) Deep perineal pouch
c) Superficial perineal pouch
d) Ischiorectal fossa

Injury to the spongy urethra allows urine and blood to collect in the superficial perineal pouch. From here, it may spread into the scrotum, penis, and lower anterior abdominal wall beneath Scarpa’s fascia, but not into the thigh due to fascia attachments. Answer: (c)

6. A 35-year-old male presents with swelling of the scrotum and penis after straddle injury. Urine collection indicates rupture of which structure?
a) Membranous urethra
b) Spongy urethra
c) Prostatic urethra
d) Bladder neck

A straddle injury often causes rupture of the spongy urethra within the bulb of the penis. Urine leaks into the superficial perineal pouch, spreading into the scrotum and lower abdominal wall due to continuity of fasciae. Answer: (b)

7. A surgeon performing perineal repair must locate the perineal body. It serves as attachment for all except:
a) Superficial transverse perinei
b) Bulbospongiosus
c) Ischiocavernosus
d) External anal sphincter

The ischiocavernosus muscle does not attach to the perineal body. It originates from the ischial tuberosity and helps maintain erection by compressing venous outflow. The other muscles contribute directly to perineal body support. Answer: (c)

8. A postpartum woman develops perineal tear extending into the superficial pouch. Which muscles are affected?
a) Ischiocavernosus and bulbospongiosus
b) Deep transverse perinei and sphincter urethrae
c) Coccygeus and levator ani
d) Obturator internus and piriformis

A tear in the superficial perineal pouch affects the ischiocavernosus, bulbospongiosus, and superficial transverse perinei muscles. These structures help maintain integrity of the perineal body, and damage can cause pelvic floor weakness and prolapse. Answer: (a)

9. A 40-year-old man has a perineal abscess below the perineal membrane. The infection lies in:
a) Deep perineal pouch
b) Superficial perineal pouch
c) Ischiorectal fossa
d) Retropubic space

An abscess below the perineal membrane lies in the superficial perineal pouch. It may spread across the midline and cause scrotal or penile swelling due to continuity of fascial layers in the perineum. Answer: (b)

10. A 25-year-old male with pelvic fracture presents with urinary retention. Rupture of membranous urethra would lead urine to collect in:
a) Superficial perineal pouch
b) Deep perineal pouch
c) Scrotum
d) Subcutaneous tissue of thigh

Rupture of the membranous urethra results in extravasation of urine into the deep perineal pouch and potentially into the retropubic space of Retzius. The perineal membrane prevents its spread into the superficial pouch. Answer: (b)

Chapter: Male Reproductive System; Topic: Spermatic Cord; Subtopic: Components and Clinical Anatomy

Keyword Definitions:

• Spermatic Cord: A bundle of structures passing from the abdomen to the testes through the inguinal canal, enclosed in fascial coverings.

• Vas Deferens: A muscular tube that transports sperm from the epididymis to the ejaculatory duct.

• Pampiniform Plexus: A network of veins surrounding the testicular artery, aiding in temperature regulation of the testes.

• Genitofemoral Nerve: A mixed nerve supplying the cremaster muscle and skin of the upper thigh and scrotum.

• Poupart’s Ligament: Another name for the inguinal ligament, forming the lower border of the abdominal wall.

Lead Question (2015): All are components of Spermatic cord except:

a) Poupart's ligament
b) Genito-femoral nerve
c) Vas deferens
d) Pampiniform plexus

Explanation: The spermatic cord contains the vas deferens, pampiniform plexus, testicular artery, cremasteric artery, and genital branch of the genitofemoral nerve. It extends from the deep inguinal ring to the testis. The Poupart’s ligament (inguinal ligament) forms a boundary of the inguinal canal but is not a part of the spermatic cord. Answer: (a)

1. Which artery does not contribute to the spermatic cord?
a) Testicular artery
b) Cremasteric artery
c) Artery to vas deferens
d) Inferior epigastric artery

The inferior epigastric artery is not a component of the spermatic cord. It gives origin to the cremasteric artery, but it lies outside the cord itself. The spermatic cord contains the testicular artery, cremasteric artery, and artery to the vas deferens. Answer: (d)

2. The pampiniform plexus drains into which vein?
a) Internal iliac vein
b) Inferior vena cava
c) Testicular vein
d) Femoral vein

The pampiniform plexus converges to form the testicular vein. On the right, it drains into the inferior vena cava; on the left, into the left renal vein. This venous arrangement helps maintain testicular temperature essential for spermatogenesis. Answer: (c)

3. Which fascial covering of the spermatic cord is derived from the transversalis fascia?
a) Cremasteric fascia
b) Internal spermatic fascia
c) External spermatic fascia
d) Dartos fascia

The internal spermatic fascia arises from the transversalis fascia at the deep inguinal ring and surrounds the cord and testes. It forms the innermost covering, followed by the cremasteric and external spermatic fasciae. Answer: (b)

4. During varicocele surgery, which structure must be preserved to prevent testicular atrophy?
a) Vas deferens
b) Pampiniform plexus
c) Testicular artery
d) Cremasteric muscle

The testicular artery provides the main blood supply to the testis. Injury during varicocele ligation can cause ischemia and testicular atrophy. The pampiniform plexus veins are ligated while preserving the artery and lymphatics. Answer: (c)

5. The genital branch of the genitofemoral nerve supplies:
a) Dartos muscle
b) Cremaster muscle
c) External oblique muscle
d) Internal oblique muscle

The genital branch of the genitofemoral nerve innervates the cremaster muscle and provides sensory fibers to the scrotal skin. It passes within the spermatic cord and is responsible for the cremasteric reflex. Answer: (b)

6. A 22-year-old male presents with a soft scrotal swelling that increases on standing and disappears when lying down. The likely cause is:
a) Hydrocele
b) Varicocele
c) Epididymitis
d) Inguinal hernia

A swelling that increases on standing and reduces when supine indicates a varicocele, which is dilation of the pampiniform plexus veins. It is more common on the left due to venous drainage into the left renal vein. Answer: (b)

7. A 30-year-old man has infertility and left scrotal heaviness. Doppler ultrasound shows dilated veins above the testis. What is the pathophysiological basis?
a) Obstruction of vas deferens
b) Incompetent testicular venous valves
c) Herniation of bowel loops
d) Arterial occlusion

A varicocele occurs due to incompetent valves in the testicular vein, leading to venous reflux and stasis. This raises scrotal temperature, impairing spermatogenesis, and may cause infertility if untreated. Answer: (b)

8. A surgeon performing hernia repair must be cautious of which structure in the spermatic cord to avoid infertility?
a) Cremasteric artery
b) Vas deferens
c) Ilioinguinal nerve
d) Dartos muscle

Inadvertent injury to the vas deferens during hernia repair can lead to obstructive infertility. It is a thick-walled muscular duct that transports sperm from the epididymis to the ejaculatory duct. Preservation is essential for reproductive function. Answer: (b)

9. A 40-year-old man undergoes varicocelectomy. Postoperatively, he develops testicular swelling due to lymphatic obstruction. Which structure’s damage caused it?
a) Vas deferens
b) Pampiniform plexus
c) Lymphatic vessels
d) Genitofemoral nerve

Postoperative testicular swelling results from injury to lymphatic vessels of the spermatic cord. They accompany the testicular artery and veins, and damage leads to lymph accumulation around the testis, forming secondary hydrocele. Answer: (c)

10. A 25-year-old male with trauma to the groin loses the cremasteric reflex. Which nerve is likely injured?
a) Iliohypogastric nerve
b) Genitofemoral nerve
c) Pudendal nerve
d) Femoral nerve

Loss of the cremasteric reflex indicates damage to the genitofemoral nerve. The genital branch stimulates contraction of the cremaster muscle, elevating the testis in response to thigh stimulation. This reflex tests integrity of L1-L2 spinal segments. Answer: (b)

Chapter: Abdomen; Topic: Inguinal Canal; Subtopic: Superficial Inguinal Ring

Keyword Definitions:

• Inguinal Canal: A short oblique passage in the lower anterior abdominal wall, transmitting the spermatic cord in males and the round ligament in females.

• Superficial Inguinal Ring: A triangular defect in the external oblique aponeurosis, forming the exit of the inguinal canal.

• Aponeurosis: A flat, broad tendon that serves as a connective tissue attachment for muscles.

• External Oblique Muscle: The largest and outermost muscle of the abdominal wall, contributing to trunk rotation and compression of abdominal contents.

Lead Question (2015): Superficial inguinal ring is a defect in the:

a) Internal oblique aponeurosis
b) External oblique aponeurosis
c) Transverse abdominis aponeurosis
d) Internal oblique muscle

Explanation: The superficial inguinal ring is an opening in the external oblique aponeurosis, forming the exit of the inguinal canal. It transmits the spermatic cord in males and the round ligament in females. The ring is bounded by medial and lateral crura of the external oblique aponeurosis. Answer: (b)

1. The deep inguinal ring is an opening in which structure?
a) External oblique aponeurosis
b) Transversalis fascia
c) Internal oblique aponeurosis
d) Linea alba

The deep inguinal ring is an opening in the transversalis fascia. It serves as the entrance to the inguinal canal and allows passage of the spermatic cord or round ligament. Its position is above the midpoint of the inguinal ligament. Answer: (b)

2. Which of the following forms the posterior wall of the inguinal canal?
a) External oblique aponeurosis
b) Transversalis fascia
c) Internal oblique muscle
d) Inguinal ligament

The posterior wall of the inguinal canal is mainly formed by the transversalis fascia, with reinforcement from the conjoint tendon medially. This wall provides strength and prevents herniation. Answer: (b)

3. The conjoint tendon is formed by the fusion of aponeuroses of:
a) External and internal oblique
b) Internal oblique and transversus abdominis
c) Transversus abdominis and rectus abdominis
d) Rectus abdominis and external oblique

The conjoint tendon is formed by the lower fibers of the internal oblique and transversus abdominis aponeuroses. It strengthens the posterior wall of the inguinal canal and supports the superficial ring area. Answer: (b)

4. In a male patient, an indirect inguinal hernia passes through which structures?
a) Only superficial ring
b) Both deep and superficial rings
c) Only deep ring
d) Femoral canal

An indirect inguinal hernia enters through the deep inguinal ring, traverses the canal, and emerges from the superficial inguinal ring. It often extends into the scrotum and is congenital due to a patent processus vaginalis. Answer: (b)

5. Inguinal canal in females transmits:
a) Round ligament of uterus
b) Ureter
c) Ovarian artery
d) Inferior epigastric vessels

In females, the inguinal canal transmits the round ligament of the uterus, a remnant of the gubernaculum. It helps maintain uterine anteversion and exits through the superficial ring, ending in the labia majora. Answer: (a)

6. A 45-year-old man presents with a swelling that increases on coughing and reduces on lying down. The hernia passes through both deep and superficial rings. Identify the type.
a) Direct inguinal hernia
b) Indirect inguinal hernia
c) Femoral hernia
d) Umbilical hernia

The described hernia passes through both deep and superficial rings, typical of an indirect inguinal hernia. It follows the embryological path of the testis and may reach the scrotum. The swelling reduces when supine. Answer: (b)

7. A patient with a direct inguinal hernia typically has a defect in:
a) Hesselbach’s triangle
b) Femoral canal
c) Deep ring
d) Pectineal ligament

A direct inguinal hernia occurs through Hesselbach’s triangle, an area bounded by the lateral edge of rectus abdominis, inferior epigastric vessels, and inguinal ligament. It protrudes directly through the posterior wall and does not pass through the deep ring. Answer: (a)

8. A surgeon repairing an inguinal hernia must take care not to injure which nerve lying near the superficial ring?
a) Genitofemoral nerve
b) Ilioinguinal nerve
c) Femoral nerve
d) Obturator nerve

The ilioinguinal nerve runs along the inguinal canal and exits through the superficial ring. During hernia repair, this nerve must be preserved to prevent sensory loss over the upper medial thigh and anterior scrotum or labia majora. Answer: (b)

9. A newborn male has a swelling in the scrotum due to a patent processus vaginalis. The condition is called:
a) Hydrocele
b) Indirect inguinal hernia
c) Cryptorchidism
d) Varicocele

A patent processus vaginalis in newborns can cause an indirect inguinal hernia or a communicating hydrocele. In this case, intestinal loops may herniate through the canal into the scrotum. Answer: (b)

10. A 60-year-old male develops a bulge above the medial part of the inguinal ligament. The hernia does not enter the scrotum. Identify the likely type.
a) Direct inguinal hernia
b) Indirect inguinal hernia
c) Femoral hernia
d) Umbilical hernia

This hernia protrudes directly through the posterior wall of the inguinal canal within Hesselbach’s triangle, not passing through the deep ring. It typically occurs in older males due to abdominal wall weakness. Answer: (a)

Chapter: Abdomen and Pelvis; Topic: Inguinal Canal' Subtopic: Deep Inguinal Ring and its Contents

Keyword Definitions:

• Deep Inguinal Ring: An opening in the transversalis fascia, located above the midpoint of the inguinal ligament, through which the spermatic cord or round ligament passes.

• Spermatic Cord: A collection of structures including vas deferens, testicular vessels, and nerves that pass through the inguinal canal to the testis.

• Ilioinguinal Nerve: A branch of the first lumbar nerve (L1) that enters the inguinal canal through the superficial ring, not the deep ring.

• Round Ligament: A fibromuscular band in females passing through the inguinal canal to support the uterus.

• Internal Spermatic Fascia: The innermost covering of the spermatic cord derived from the transversalis fascia at the deep inguinal ring.

Lead Question (2015)
All pass through deep inguinal ring, EXCEPT?
a) Spermatic cord
b) Internal spermatic fascia
c) Round ligament
d) Ilioinguinal nerve

Explanation: The deep inguinal ring transmits the spermatic cord in males and the round ligament in females. The internal spermatic fascia is derived from the transversalis fascia at this ring. However, the ilioinguinal nerve does not pass through the deep inguinal ring but enters the canal midway and exits via the superficial ring. Hence, the correct answer is (d) Ilioinguinal nerve.

1. Which structure forms the anterior wall of the inguinal canal?
a) Transversalis fascia
b) External oblique aponeurosis
c) Internal oblique muscle
d) Fascia transversalis and peritoneum

Explanation: The anterior wall of the inguinal canal is mainly formed by the external oblique aponeurosis and is reinforced laterally by fibers of the internal oblique muscle. This wall provides support and prevents herniation. Hence, the answer is (b) External oblique aponeurosis.

2. The posterior wall of the inguinal canal is formed by -
a) Transversalis fascia
b) Conjoint tendon
c) Both a and b
d) Internal oblique muscle

Explanation: The posterior wall is mainly formed by the transversalis fascia and reinforced medially by the conjoint tendon (fusion of internal oblique and transversus abdominis aponeuroses). Hence, the answer is (c) Both a and b.

3. A 30-year-old male presents with an indirect inguinal hernia. The hernial sac enters through which structure?
a) Deep inguinal ring
b) Superficial inguinal ring
c) Hesselbach’s triangle
d) Femoral canal

Explanation: An indirect inguinal hernia occurs when abdominal contents herniate through the deep inguinal ring, traveling along the spermatic cord, and may reach the scrotum. It is lateral to the inferior epigastric vessels. Hence, the answer is (a) Deep inguinal ring.

4. Direct inguinal hernia occurs through -
a) Deep inguinal ring
b) Superficial inguinal ring
c) Posterior wall of inguinal canal
d) Femoral canal

Explanation: Direct inguinal hernia occurs through a weakness in the posterior wall of the inguinal canal within Hesselbach’s triangle, medial to the inferior epigastric vessels. It usually does not reach the scrotum. Hence, the answer is (c) Posterior wall of inguinal canal.

5. Which layer gives rise to the cremasteric muscle and fascia?
a) External oblique aponeurosis
b) Internal oblique muscle
c) Transversus abdominis
d) Transversalis fascia

Explanation: The cremasteric muscle and fascia are derived from the internal oblique muscle layer as the spermatic cord passes through the inguinal canal. The cremaster muscle elevates the testis during temperature changes. Hence, the answer is (b) Internal oblique muscle.

6. Which nerve supplies the cremasteric muscle?
a) Ilioinguinal nerve
b) Genital branch of genitofemoral nerve
c) Femoral nerve
d) Pudendal nerve

Explanation: The genital branch of the genitofemoral nerve supplies the cremasteric muscle. This nerve also carries afferent fibers for the cremasteric reflex. Hence, the answer is (b) Genital branch of genitofemoral nerve.

7. A patient presents with absence of the cremasteric reflex. The lesion is likely in -
a) L1 spinal segment
b) L2 spinal segment
c) L3 spinal segment
d) S2 spinal segment

Explanation: The cremasteric reflex involves the sensory input from the ilioinguinal nerve (L1) and motor output through the genital branch of the genitofemoral nerve (L1–L2). Loss of reflex indicates damage to L1–L2 segments. Hence, the answer is (b) L2 spinal segment.

8. Which structure forms the roof of the inguinal canal?
a) Transversus abdominis and internal oblique muscles
b) External oblique aponeurosis
c) Conjoint tendon
d) Transversalis fascia

Explanation: The roof of the inguinal canal is formed by arching fibers of the transversus abdominis and internal oblique muscles. These fibers provide dynamic support during increased intra-abdominal pressure. Hence, the answer is (a) Transversus abdominis and internal oblique muscles.

9. The superficial inguinal ring is an opening in the -
a) Transversalis fascia
b) Internal oblique muscle
c) External oblique aponeurosis
d) Conjoint tendon

Explanation: The superficial inguinal ring is a triangular gap in the external oblique aponeurosis located just above the pubic crest. It allows exit of the spermatic cord or round ligament. Hence, the answer is (c) External oblique aponeurosis.

10. In a male child with a patent processus vaginalis, which hernia type is most likely?
a) Direct inguinal hernia
b) Indirect inguinal hernia
c) Umbilical hernia
d) Femoral hernia

Explanation: A patent processus vaginalis creates a congenital communication between the peritoneal cavity and scrotum, predisposing to an indirect inguinal hernia. The hernia follows the same path as the spermatic cord. Hence, the answer is (b) Indirect inguinal hernia.

Chapter: Pelvis and Perineum; Topic: Nerve Supply of Pelvic Organs; Subtopic: Innervation of Uterus

Keyword Definitions:

• Labour pain: Intense uterine contractions during childbirth transmitted through visceral afferent fibers.

• Sympathetic nerves: Fibers arising from thoracolumbar segments that carry pain from the uterine body during labour.

• Parasympathetic nerves: Fibers from sacral outflow (S2–S4) mainly supplying cervix and vagina.

• Pudendal nerve: Somatic nerve supplying perineum and external genitalia, involved in somatic pain.

• Splanchnic nerves: Visceral nerves carrying sympathetic and sensory fibers from abdominal and pelvic organs.

Lead Question (2015):
Labour pain in uterus is carried by
a) Parasympathetic nerves
b) Sympathetic nerves
c) Pudendal nerve
d) Splanchnic nerve

Explanation: The correct answer is b) Sympathetic nerves. Labour pain originates from uterine contractions and cervical dilation. Pain from the uterine body is transmitted via sympathetic fibers through the hypogastric plexus and enters the spinal cord at T10–L1 levels. Pain from the cervix and perineum, however, is carried by parasympathetic and pudendal nerves respectively.

1) Pain from uterine contractions during first stage of labour is transmitted via:
a) T10–L1 sympathetic fibers
b) S2–S4 parasympathetic fibers
c) Pudendal nerve
d) Femoral nerve

Explanation: The answer is a) T10–L1 sympathetic fibers. During the first stage of labour, pain arises from stretching of the uterine wall and is transmitted through sympathetic afferents accompanying the hypogastric nerves to T10–L1 spinal segments. This explains why epidural blocks at these levels effectively relieve early labour pain.

2) Pain during the second stage of labour is mainly transmitted by:
a) Pudendal nerve
b) Sympathetic nerves
c) Pelvic splanchnic nerves
d) Ilioinguinal nerve

Explanation: The correct answer is a) Pudendal nerve. In the second stage of labour, pain is somatic due to stretching of perineal tissues and vaginal walls. This pain is transmitted by the pudendal nerve (S2–S4). Pudendal block provides effective anesthesia for perineal delivery procedures and episiotomy.

3) Which nerve fibers carry pain from the cervix during labour?
a) Parasympathetic fibers from S2–S4
b) Sympathetic fibers from T12–L1
c) Pudendal nerve
d) Iliohypogastric nerve

Explanation: The answer is a) Parasympathetic fibers from S2–S4. Cervical dilation pain is transmitted by parasympathetic afferents through pelvic splanchnic nerves (S2–S4). This explains why a caudal block that anesthetizes these sacral roots helps relieve cervical pain in later stages of labour.

4) In epidural anesthesia for labour, which spinal segments are targeted to block uterine contraction pain?
a) T10–L1
b) L4–S1
c) S2–S4
d) T4–T6

Explanation: The correct answer is a) T10–L1. Blocking these segments relieves pain from uterine contractions during the first stage of labour. For complete perineal analgesia during the second stage, the block is extended to include S2–S4 roots that carry pudendal nerve fibers.

5) A woman in early labour complains of pain in the lower abdomen radiating to the back. The nerve pathway involved is:
a) Sympathetic afferents via hypogastric plexus
b) Pudendal nerve
c) Pelvic splanchnic nerves
d) Somatic fibers from iliohypogastric nerve

Explanation: The answer is a) Sympathetic afferents via hypogastric plexus. Visceral pain from uterine contractions is referred to the lower abdomen and back due to shared T10–L1 dermatomes. These sympathetic afferents travel through the hypogastric and aortic plexuses to the spinal cord.

6) Which of the following statements about pudendal nerve is TRUE?
a) It carries somatic pain from perineum
b) It supplies the uterine body
c) It originates from T10–L1
d) It is purely parasympathetic

Explanation: The correct answer is a) It carries somatic pain from perineum. The pudendal nerve is derived from sacral spinal nerves (S2–S4) and supplies motor and sensory innervation to the perineum, external anal sphincter, and genitalia. It is crucial in transmitting somatic pain during the second stage of labour.

7) Pain from the uterine fundus is referred to which dermatome level?
a) T10–L1
b) L4–L5
c) S1–S3
d) T4–T6

Explanation: The correct answer is a) T10–L1. The uterine fundus is supplied by sympathetic afferents that enter the spinal cord at T10–L1. Therefore, pain from uterine contractions is referred to the lower abdomen and back corresponding to these dermatomes, a typical presentation during early labour.

8) Which type of nerve fibers transmit visceral pain from the uterus?
a) Unmyelinated C fibers
b) Myelinated A-beta fibers
c) Myelinated A-delta fibers
d) Somatic motor fibers

Explanation: The correct answer is a) Unmyelinated C fibers. Labour pain is transmitted via unmyelinated visceral C fibers associated with sympathetic afferents. These fibers conduct slow, dull, and diffuse pain sensations that are poorly localized, typical of visceral pain from uterine contractions.

9) During caudal anesthesia, which nerve fibers are blocked to relieve perineal pain?
a) Pudendal and pelvic splanchnic nerves
b) Femoral and obturator nerves
c) Iliohypogastric nerve
d) Sympathetic chain fibers

Explanation: The answer is a) Pudendal and pelvic splanchnic nerves. Caudal anesthesia blocks sacral nerve roots (S2–S4), providing effective analgesia for perineal pain during childbirth. It targets both pudendal (somatic) and pelvic splanchnic (visceral parasympathetic) nerves, useful in second-stage labour pain relief.

10) A multiparous woman in labour experiences pain not relieved by epidural block at T10–L1. The cause is likely unblocked:
a) Pudendal nerve
b) Iliohypogastric nerve
c) Femoral nerve
d) Genitofemoral nerve

Explanation: The correct answer is a) Pudendal nerve. An epidural block covering T10–L1 levels relieves visceral pain from uterine contractions but not somatic pain from perineal distension. The pudendal nerve (S2–S4) carries perineal pain; thus, a supplementary pudendal block is required for complete analgesia during delivery.

Chapter: Abdomen; Topic: Peritoneum and Mesenteries; Subtopic: Transverse Mesocolon

Keyword Definitions:

• Transverse Mesocolon: A double layer of peritoneum that suspends the transverse colon from the posterior abdominal wall.

• Middle Colic Artery: A branch of the superior mesenteric artery supplying the transverse colon through the transverse mesocolon.

• Right Colic Artery: Supplies the ascending colon and arises from the superior mesenteric artery.

• Left Colic Artery: Branch of the inferior mesenteric artery supplying the descending colon.

• Iliocolic Artery: Supplies the terminal ileum, cecum, and appendix; arises from the superior mesenteric artery.

Lead Question (2015):
In which of the following vessels transverse mesocolon is seen?
a) Right colic artery
b) Left colic artery
c) Middle colic artery
d) Iliocolic artery

Explanation: The correct answer is Middle colic artery. The transverse mesocolon is a peritoneal fold attaching the transverse colon to the posterior abdominal wall. It encloses the middle colic vessels, branches of the superior mesenteric artery. These vessels supply most of the transverse colon, making this region crucial in colonic surgeries and vascular anastomoses.

1) The middle colic artery is a branch of which major artery?
a) Inferior mesenteric artery
b) Superior mesenteric artery
c) Celiac trunk
d) Common iliac artery

Explanation: The answer is b) Superior mesenteric artery. The middle colic artery arises from the superior mesenteric artery just below the pancreas and supplies the transverse colon. It divides into right and left branches, forming anastomoses with right and left colic arteries, maintaining collateral circulation in the colon.

2) The transverse mesocolon divides the abdominal cavity into which compartments?
a) Supra- and infracolic compartments
b) Right and left paracolic gutters
c) Anterior and posterior peritoneal cavities
d) Greater and lesser sacs

Explanation: The correct answer is a) Supra- and infracolic compartments. The transverse mesocolon forms an important peritoneal partition dividing the peritoneal cavity into supracolic and infracolic compartments. The supracolic compartment contains the liver, stomach, and spleen, while the infracolic compartment contains the intestines and mesentery.

3) During a colectomy, which vessel must be ligated within the transverse mesocolon?
a) Middle colic artery
b) Left gastric artery
c) Splenic artery
d) Gastroduodenal artery

Explanation: The answer is a) Middle colic artery. In transverse colectomy, the middle colic artery is carefully identified and ligated within the transverse mesocolon to prevent bleeding and ensure proper resection margins. Preservation of collateral circulation between right and left colic arteries is essential for postoperative healing.

4) A 60-year-old man undergoing pancreatic surgery may have injury to which vessel within the transverse mesocolon?
a) Middle colic artery
b) Left gastric artery
c) Inferior mesenteric artery
d) Splenic vein

Explanation: The correct answer is a) Middle colic artery. The transverse mesocolon crosses the anterior surface of the pancreas, making the middle colic vessels vulnerable during pancreatic surgeries. Injury can cause colonic ischemia or necrosis; hence, surgical awareness of mesocolic vascular anatomy is crucial for safe dissection.

5) The root of the transverse mesocolon crosses which structures posteriorly?
a) Second part of duodenum and pancreas
b) Spleen and left kidney
c) Liver and gallbladder
d) Inferior vena cava and right ureter

Explanation: The answer is a) Second part of duodenum and pancreas. The root of the transverse mesocolon passes across the head and anterior border of the pancreas and the second part of the duodenum. This anatomical relation is vital during surgical mobilization of the transverse colon and in understanding spread of infections or malignancies.

6) The lymphatic drainage of the transverse mesocolon primarily follows which vessel?
a) Middle colic artery
b) Inferior mesenteric artery
c) Left gastric artery
d) Splenic artery

Explanation: The correct answer is a) Middle colic artery. Lymph nodes along the middle colic artery drain lymph from the transverse colon. These nodes eventually drain into the superior mesenteric lymph nodes. Proper identification of these nodes is essential during oncologic resections for accurate staging and clearance of colon carcinoma.

7) In a CT scan, the transverse mesocolon appears as a fold connecting which two organs?
a) Transverse colon and posterior abdominal wall
b) Ascending colon and liver
c) Descending colon and spleen
d) Cecum and appendix

Explanation: The answer is a) Transverse colon and posterior abdominal wall. On imaging, the transverse mesocolon appears as a double peritoneal fold extending from the posterior abdominal wall to the transverse colon. It contains middle colic vessels, lymphatics, and nerves, playing a key role in supporting the transverse colon anatomically and functionally.

8) A surgeon retracting the transverse colon upward exposes which peritoneal compartment?
a) Infracolic compartment
b) Supracolic compartment
c) Pelvic cavity
d) Subphrenic space

Explanation: The correct answer is b) Supracolic compartment. When the transverse colon is lifted upwards, the transverse mesocolon moves with it, exposing the supracolic compartment. This compartment contains major organs like the stomach, liver, and spleen, and is of great surgical importance during upper abdominal operations.

9) During embryological development, the transverse mesocolon originates from which mesentery?
a) Dorsal mesentery
b) Ventral mesentery
c) Mesoduodenum
d) Mesogastrium

Explanation: The answer is a) Dorsal mesentery. The transverse mesocolon develops from the dorsal mesentery of the midgut. It becomes attached to the posterior abdominal wall and fuses partially with the greater omentum, reflecting the complex peritoneal rearrangements during embryogenesis of the gastrointestinal tract.

10) A 50-year-old woman with carcinoma of the transverse colon shows lymphatic spread through nodes located in?
a) Transverse mesocolon
b) Mesentery of small intestine
c) Lesser omentum
d) Sigmoid mesocolon

Explanation: The correct answer is a) Transverse mesocolon. Lymphatic drainage of the transverse colon primarily occurs via the transverse mesocolon, where lymph nodes accompany the middle colic vessels. In colon cancer, metastasis through these nodes is common, emphasizing the need for complete mesocolic excision during colectomy to ensure oncologic safety.

Chapter: Male Reproductive System; Topic: Seminal Vesicles; Subtopic: Anatomy and Physiology

Keyword Definitions:

Seminal Vesicles: Paired glands posterior to bladder producing about 60% of seminal fluid rich in fructose and prostaglandins.

Fructose: A sugar that provides energy for sperm motility.

Prostate: A gland surrounding the urethra contributing secretions to semen.

Seminal Fluid: The liquid medium in which sperm are transported during ejaculation.

Lead Question - 2015 & 2012

FALSE for seminal vesicles:

a) Contains large amount of fructose

b) Stores sperms

c) Situated on either side near prostate

d) Secretion of seminal vesicle gives mucoid consistency to semen

Explanation:

Answer: b) Stores sperms

Seminal vesicles do not store sperms; they secrete a fructose-rich, alkaline fluid that nourishes sperm and forms a major portion of semen. The sperm are stored mainly in the epididymis and vas deferens. The secretion from seminal vesicles adds volume, viscosity, and nutrients to semen, ensuring sperm viability and motility during ejaculation.

1. Seminal vesicles open into which structure?

a) Ejaculatory duct

b) Prostatic urethra

c) Membranous urethra

d) Bulbourethral gland

Explanation:

Answer: a) Ejaculatory duct

The duct of each seminal vesicle joins the ductus deferens to form the ejaculatory duct, which passes through the prostate to open into the prostatic urethra. This junction allows seminal vesicle secretions to mix with sperm from the vas deferens before ejaculation, contributing to semen composition and pH regulation.

2. The secretion of seminal vesicle is rich in:

a) Protein

b) Fructose

c) Glucose

d) Urea

Explanation:

Answer: b) Fructose

Seminal vesicle secretion is rich in fructose, which provides an energy source for spermatozoa. It also contains prostaglandins and clotting proteins. Fructose is essential for sperm motility, enabling the sperm to survive and move through the female reproductive tract. Deficiency of fructose may result in reduced fertility.

3. Which of the following is NOT secreted by seminal vesicles?

a) Prostaglandins

b) Fructose

c) Fibrinogen

d) Spermine

Explanation:

Answer: d) Spermine

Spermine is secreted by the prostate gland, not by seminal vesicles. Seminal vesicles mainly secrete fructose, prostaglandins, and fibrinogen-like proteins, contributing to semen coagulation and nourishment of sperm. These secretions enhance sperm survival and facilitate fertilization by supporting sperm motility in the female tract.

4. Clinical: A 35-year-old male with ejaculatory duct obstruction shows low semen volume but normal sperm count. Which gland is likely affected?

a) Prostate

b) Seminal vesicle

c) Bulbourethral gland

d) Epididymis

Explanation:

Answer: b) Seminal vesicle

Seminal vesicle obstruction leads to decreased semen volume as it produces nearly 60% of seminal fluid. Sperm count remains normal because sperm production occurs in the testes. Obstruction can result in infertility due to reduced seminal plasma volume and decreased fructose concentration affecting sperm motility and energy supply.

5. The ejaculatory duct is formed by the union of:

a) Vas deferens and urethra

b) Vas deferens and duct of seminal vesicle

c) Epididymis and vas deferens

d) Urethra and prostate

Explanation:

Answer: b) Vas deferens and duct of seminal vesicle

Each ejaculatory duct is formed by the union of the ampulla of vas deferens and the duct of seminal vesicle. This duct passes through the prostate and opens into the prostatic urethra. Its main function is to transport semen during ejaculation by combining sperm with seminal vesicle fluid.

6. Clinical: A patient with congenital absence of seminal vesicles will have which of the following abnormalities?

a) Azoospermia

b) Low semen fructose

c) High semen volume

d) Increased sperm motility

Explanation:

Answer: b) Low semen fructose

Seminal vesicles are the major source of fructose in semen. Absence of seminal vesicles results in low fructose concentration, leading to reduced sperm motility and fertility issues. Sperm production remains unaffected because spermatogenesis occurs in testes, but sperm lose the nutrient-rich environment necessary for effective fertilization.

7. Seminal vesicle lies posterior to:

a) Urinary bladder

b) Prostate

c) Rectum

d) Pubic symphysis

Explanation:

Answer: a) Urinary bladder

Seminal vesicles are paired sac-like glands located posterior to the urinary bladder and anterior to the rectum. Their ducts join the vas deferens to form ejaculatory ducts. Their location is clinically important in rectal examinations, as enlargement or tenderness may indicate inflammation or obstruction of seminal vesicles.

8. Clinical: During prostatectomy, damage to seminal vesicles may result in:

a) Impotence

b) Reduced semen volume

c) Testicular atrophy

d) Urinary retention

Explanation:

Answer: b) Reduced semen volume

Seminal vesicles contribute significantly to semen volume. Surgical injury or removal can drastically reduce seminal fluid secretion, leading to low semen volume and infertility. However, it does not directly cause impotence since erection is mediated by neural mechanisms and vascular function, not seminal secretion.

9. Which of the following statements about seminal vesicles is FALSE?

a) They are paired glands

b) They lie anterior to rectum

c) Their secretion contains sperm

d) They open into ejaculatory duct

Explanation:

Answer: c) Their secretion contains sperm

Seminal vesicles do not contain sperm; sperm come from testes via vas deferens. Seminal vesicles contribute secretions that nourish and activate sperm. These secretions mix with sperm only after reaching ejaculatory ducts, forming semen just before ejaculation. Thus, the glands themselves contain no spermatozoa.

10. Seminal vesicle secretion contributes to semen alkalinity due to presence of:

a) Citric acid

b) Phosphates and bicarbonates

c) Lactic acid

d) Cholesterol

Explanation:

Answer: b) Phosphates and bicarbonates

Seminal vesicle secretion contains alkaline substances like bicarbonates and phosphates, which neutralize the acidic environment of the female vagina. This ensures sperm viability and enhances motility. The alkaline nature of seminal fluid is crucial for maintaining optimal pH for fertilization and preventing sperm damage.

11. Clinical: Infection of seminal vesicles is known as:

a) Vesiculitis

b) Epididymitis

c) Orchitis

d) Prostatitis

Explanation:

Answer: a) Vesiculitis

Vesiculitis refers to inflammation of the seminal vesicles, commonly due to bacterial infections spreading from the prostate or urethra. Symptoms include painful ejaculation, fever, and hematospermia (blood in semen). Chronic vesiculitis can affect semen composition and fertility due to impaired secretion and altered pH balance.

Chapter: Pelvis;   Topic: Urogenital System;   Subtopic: Female Homologues of Male Reproductive Organs 

Keyword Definitions: 

• Prostate Gland: A male accessory gland producing seminal fluid that nourishes sperm. 

• Skene’s Glands: Also known as paraurethral glands; small glands located near the female urethra, homologous to the male prostate. 

• Homologous Structures: Organs that develop from the same embryonic tissues in both sexes but differ functionally. 

• Bartholin’s Gland: Large paired glands in the vestibule providing lubrication during intercourse. 

• Bulbourethral Gland: Male gland secreting mucus-like fluid for urethral lubrication before ejaculation. 

Lead Question - 2015

Prostate analogue in female is -

a) Skene gland

b) Bulbourethral gland

c) Great vestibular gland

d) Bartholin's gland

Explanation: The Skene’s glands (paraurethral glands) in females are homologous to the prostate gland in males. They secrete a fluid similar in composition to prostatic fluid and open near the urethral meatus. Their development originates from the urogenital sinus, the same as the prostate. Answer: Skene gland.

1. The male homolog of Bartholin’s gland is:

a) Bulbourethral gland

b) Prostate

c) Seminal vesicle

d) Cowper’s duct

Explanation: The Bartholin’s gland in females is homologous to the bulbourethral (Cowper’s) gland in males. Both develop from the urogenital sinus and secrete mucus to lubricate the genital tract during sexual activity. Answer: Bulbourethral gland.

2. The embryological origin of the prostate is:

a) Mesonephric duct

b) Paramesonephric duct

c) Urogenital sinus

d) Cloaca

Explanation: The prostate gland arises as an outgrowth from the urogenital sinus epithelium around the 10th week of fetal life. The surrounding mesenchyme forms its stroma. Similarly, female Skene’s glands share the same embryonic source. Answer: Urogenital sinus.

3. In females, Skene’s glands open into:

a) Vagina

b) Urethra near external meatus

c) Vestibule

d) Cervical canal

Explanation: The Skene’s glands open into the urethra near the external meatus. These glands secrete an antimicrobial fluid and help maintain urethral health. Their infection can mimic urinary tract infection symptoms. Answer: Urethra near external meatus.

4. The female structure homologous to the scrotum is:

a) Labia minora

b) Labia majora

c) Vestibule

d) Mons pubis

Explanation: The labia majora in females develop from the same embryological folds that form the scrotum in males. Both are derived from the labioscrotal swellings. Answer: Labia majora.

5. The female homolog of penis is:

a) Labia minora

b) Vestibule

c) Clitoris

d) Mons pubis

Explanation: The clitoris in females is homologous to the penis in males. Both develop from the genital tubercle and contain erectile tissue. Answer: Clitoris.

6. A woman presents with a paraurethral mass discharging pus. The likely infected gland is:

a) Bartholin’s gland

b) Skene’s gland

c) Vestibular gland

d) Bulbourethral gland

Explanation: Infection of the Skene’s gland (paraurethral abscess) causes periurethral swelling and pus discharge near the urethral meatus. Common pathogens include E. coli and Gonococcus. Answer: Skene’s gland.

7. Bartholin’s cyst is located at:

a) Upper vaginal wall

b) Vestibule at 5 and 7 o’clock positions

c) Around urethral meatus

d) Posterior fornix

Explanation: Bartholin’s glands lie at the posterolateral part of the vaginal opening (5 and 7 o’clock positions). Blockage of its duct leads to cyst formation. Answer: Vestibule at 5 and 7 o’clock positions.

8. Which of the following female structures develops from the mesonephric duct?

a) Uterine tube

b) Uterus

c) Gartner’s duct

d) Ovary

Explanation: The Gartner’s duct (remnant of mesonephric duct) may persist along the vaginal wall. In males, this duct forms the vas deferens and seminal vesicle. Answer: Gartner’s duct.

9. Which hormone influences prostate development in males?

a) Estrogen

b) Testosterone

c) Dihydrotestosterone (DHT)

d) Progesterone

Explanation: The development of the prostate gland requires dihydrotestosterone (DHT), a potent androgen derived from testosterone by 5α-reductase. In its absence, prostate and external genitalia fail to differentiate. Answer: Dihydrotestosterone (DHT).

10. Skene’s glands in females are located:

a) Posterior to vagina

b) Lateral to urethra

c) Deep to clitoris

d) Within vestibule

Explanation: The Skene’s glands are situated lateral to the urethra, embedded in the anterior vaginal wall. They secrete fluid during sexual arousal and drain into the urethral orifice. Answer: Lateral to urethra.

11. A tumor in female paraurethral glands is analogous to which male cancer?

a) Penile carcinoma

b) Prostate carcinoma

c) Testicular tumor

d) Epididymal cyst

Explanation: Malignancy arising from Skene’s glands is rare but histologically resembles prostate carcinoma, confirming their homology. Such cases may show PSA and PAP positivity on immunostaining. Answer: Prostate carcinoma.

Chapter: Pelvis; Topic: Female Reproductive System; Subtopic: Lymphatic Drainage of Ovary

Keyword Definitions:

• Ovary: Female gonad producing ova and hormones (estrogen, progesterone).

• Lymphatic drainage: Flow of lymph from organs to lymph nodes through defined vessels.

• Paraaortic lymph nodes: Nodes located along the abdominal aorta receiving drainage from ovaries, kidneys, and uterus.

• Inguinal lymph nodes: Nodes in the groin area draining perineum and external genitalia.

• Obturator lymph nodes: Nodes near obturator vessels draining pelvic viscera.

Lead Question - 2015

Lymphatic drainage of ovary?

a) Deep inguinal

b) Superficial inguinal

c) Obturator

d) Paraaortic

Explanation: The lymphatic drainage of the ovary is through vessels that accompany the ovarian vessels to the paraaortic (lumbar) lymph nodes at the level of L1. This is because the ovaries originate in the posterior abdominal wall before descending into the pelvis during development. Hence, the correct answer is d) Paraaortic.

1. Which lymph nodes receive lymph from the uterus fundus along the ovarian vessels?

a) Internal iliac

b) External iliac

c) Paraaortic

d) Deep inguinal

Explanation: The fundus of the uterus drains partly along the ovarian vessels into the paraaortic lymph nodes. This pathway is significant during metastasis of endometrial carcinoma, where cancer may spread to upper abdominal nodes. Hence, the correct answer is c) Paraaortic.

2. Lymph from the lower part of the vagina drains into:

a) Paraaortic nodes

b) External iliac nodes

c) Internal iliac and superficial inguinal nodes

d) Deep inguinal nodes

Explanation: The lower part of the vagina drains into internal iliac and superficial inguinal nodes. The dual drainage is important in understanding the spread of vaginal carcinoma and infections. Hence, the correct answer is c) Internal iliac and superficial inguinal nodes.

3. Clinical case: A patient with ovarian carcinoma presents with enlarged nodes near the renal hilum. Which lymph nodes are involved?

a) Internal iliac

b) Paraaortic

c) External iliac

d) Superficial inguinal

Explanation: Ovarian carcinoma typically spreads to paraaortic lymph nodes near the renal hilum because ovarian lymphatics follow the ovarian vessels that ascend to the aortic region. This is a key diagnostic feature in imaging. Hence, the correct answer is b) Paraaortic.

4. Which of the following organs share similar lymphatic drainage as the ovary?

a) Uterus

b) Kidney

c) Rectum

d) Vagina

Explanation: Both ovary and kidney drain into paraaortic lymph nodes since both originate from the posterior abdominal wall embryologically. Understanding this helps trace metastatic spread patterns. Hence, the correct answer is b) Kidney.

5. Which structure carries ovarian lymphatics to paraaortic nodes?

a) Broad ligament

b) Suspensory ligament of ovary

c) Round ligament of uterus

d) Ovarian ligament

Explanation: Ovarian lymphatics travel through the suspensory ligament of the ovary (infundibulopelvic ligament) along with ovarian vessels to reach the paraaortic nodes. This ligament connects the ovary to the lateral pelvic wall. Hence, the correct answer is b) Suspensory ligament of ovary.

6. Clinical case: A 45-year-old woman with ovarian carcinoma shows paraaortic node metastasis. What is the route of lymphatic spread?

a) Along round ligament

b) Along ovarian vessels

c) Along uterine vessels

d) Along uterosacral ligament

Explanation: Ovarian lymphatics follow the course of ovarian vessels through the suspensory ligament to paraaortic nodes. This route allows tumor cells to spread to retroperitoneal nodes, detectable on CT scans. Hence, the correct answer is b) Along ovarian vessels.

7. Which lymph nodes drain the cervix of the uterus?

a) Paraaortic

b) External and internal iliac

c) Superficial inguinal

d) Deep inguinal

Explanation: The cervix drains into both external and internal iliac lymph nodes, a key pathway for cervical carcinoma spread. Hence, the correct answer is b) External and internal iliac.

8. Which lymph nodes receive lymph from the round ligament of uterus?

a) Deep inguinal

b) Paraaortic

c) Internal iliac

d) Obturator

Explanation: The round ligament passes through the inguinal canal and ends in the labia majora, so its lymphatic drainage terminates in the superficial inguinal nodes. This connection explains inguinal metastasis in uterine cancers. Hence, the correct answer is a) Deep inguinal.

9. Lymph from the body of uterus mainly drains to:

a) External iliac nodes

b) Superficial inguinal nodes

c) Paraaortic nodes

d) Obturator nodes

Explanation: The body of the uterus drains mainly into external iliac lymph nodes, with some lymph reaching paraaortic nodes via ovarian vessels. This dual drainage is important for surgical staging. Hence, the correct answer is a) External iliac nodes.

10. Clinical case: A woman with uterine carcinoma presents with palpable inguinal nodes. Which structure provides this lymphatic connection?

a) Ovarian ligament

b) Round ligament

c) Suspensory ligament of ovary

d) Uterosacral ligament

Explanation: The round ligament provides the connection between the uterus and the superficial inguinal lymph nodes through the inguinal canal. This explains why uterine cancers can spread to groin nodes. Hence, the correct answer is b) Round ligament.

Chapter: Anatomy of the Breast; Topic: Mammary Gland; Subtopic: Lobes and Duct System

Keyword Definitions:

• Breast: A modified sweat gland located in the pectoral region that functions in milk secretion in females.

• Lobes: Distinct glandular units of the breast, each draining through a separate lactiferous duct.

• Lactiferous Ducts: Tubes that carry milk from the lobes to the nipple.

• Areola: Pigmented area surrounding the nipple containing sebaceous glands.

Lead Question – 2015

Number of lobes in breast

a) 5

b) 10

c) 15

d) 30

Explanation: The breast typically has 15 to 20 lobes, each made up of numerous lobules that contain alveoli for milk secretion. Each lobe opens through a separate lactiferous duct onto the nipple. The number may vary slightly between individuals but functionally averages around 15–20. Answer: (c) 15.

1. The functional unit of the breast is:

a) Lobe

b) Lobule

c) Alveolus

d) Lactiferous duct

Explanation: The alveolus is the functional unit of the breast, responsible for milk synthesis and secretion under the influence of prolactin. Each lobule contains multiple alveoli that drain into intralobular ducts, which then form larger ducts converging toward the nipple. Answer: (c) Alveolus.

2. The breast lies over which muscle?

a) Serratus anterior

b) Pectoralis major

c) Latissimus dorsi

d) External oblique

Explanation: The breast rests on the deep fascia covering the pectoralis major muscle and partly on the serratus anterior. A layer of loose connective tissue called the retromammary space allows movement of the breast over the pectoral fascia. Answer: (b) Pectoralis major.

3. Which hormone primarily stimulates milk secretion?

a) Estrogen

b) Progesterone

c) Prolactin

d) Oxytocin

Explanation: Prolactin, secreted by the anterior pituitary gland, promotes milk secretion from alveolar epithelial cells. Estrogen and progesterone prepare the gland for lactation but inhibit secretion until after delivery when their levels drop. Answer: (c) Prolactin.

4. Which structure drains milk from each breast lobe to the nipple?

a) Alveolar duct

b) Intralobular duct

c) Lactiferous duct

d) Areolar gland

Explanation: Each breast lobe is drained by a lactiferous duct, which widens into a lactiferous sinus beneath the areola before opening at the nipple. This duct system ensures milk delivery during lactation. Answer: (c) Lactiferous duct.

5. Which ligament supports the breast structure?

a) Cooper’s ligament

b) Suspensory ligament of ovary

c) Round ligament

d) Pectoral ligament

Explanation: Cooper’s ligaments (suspensory ligaments) are fibrous connective tissue bands that anchor the breast to the pectoral fascia and skin, maintaining shape. Their contraction during carcinoma causes skin dimpling. Answer: (a) Cooper’s ligament.

6. Clinical: A woman presents with nipple retraction. Which structure is likely involved?

a) Lactiferous ducts

b) Cooper’s ligaments

c) Retromammary space

d) Areolar glands

Explanation: Retraction of the nipple often results from fibrosis or malignancy involving the lactiferous ducts. The fibrosis pulls the ducts inward, causing visible retraction. It is a significant sign of breast carcinoma. Answer: (a) Lactiferous ducts.

7. Lymph from the lateral quadrant of the breast mainly drains into:

a) Parasternal nodes

b) Axillary nodes

c) Infraclavicular nodes

d) Supraclavicular nodes

Explanation: Approximately 75% of breast lymph drains into axillary lymph nodes, especially the anterior (pectoral) group. The medial quadrants drain into parasternal nodes. Understanding lymphatic drainage is crucial in assessing metastasis. Answer: (b) Axillary nodes.

8. During radical mastectomy, which nerve should be preserved to avoid scapular winging?

a) Long thoracic nerve

b) Thoracodorsal nerve

c) Intercostobrachial nerve

d) Suprascapular nerve

Explanation: The long thoracic nerve supplies the serratus anterior. Injury leads to scapular winging due to paralysis of the muscle, preventing the scapula from adhering to the thoracic wall. Answer: (a) Long thoracic nerve.

9. Clinical: A lactating mother presents with a painful lump and fever. Likely diagnosis is:

a) Fibroadenoma

b) Mastitis

c) Carcinoma

d) Lipoma

Explanation: Mastitis is an inflammatory condition of the breast, often due to Staphylococcus aureus infection during lactation. It causes localized pain, redness, and fever. Proper hygiene and drainage are vital for management. Answer: (b) Mastitis.

10. Which quadrant of the breast is most prone to carcinoma?

a) Upper outer

b) Lower outer

c) Upper inner

d) Lower inner

Explanation: The upper outer quadrant of the breast is the most frequent site of carcinoma because it contains the highest proportion of glandular tissue and lymphatic drainage toward the axilla, facilitating metastasis. Answer: (a) Upper outer.

11. Clinical: In carcinoma of the breast, peau d’orange appearance occurs due to:

a) Blocked sebaceous glands

b) Lymphatic obstruction

c) Fat necrosis

d) Cooper’s ligament hypertrophy

Explanation: Peau d’orange (orange peel) appearance in breast carcinoma is due to lymphatic obstruction causing edema of the skin. The tethering of skin by Cooper’s ligaments exaggerates the dimpling effect, giving the surface an orange-like texture. Answer: (b) Lymphatic obstruction. 

Topic: Puberty and Secondary Sexual Characteristics; Subtopic: Hormonal Control of Pubarche

Keyword Definitions:

• Pubarche: The onset of pubic and axillary hair growth during puberty, resulting from increased secretion of adrenal androgens.

• Adrenarche: The phase before puberty when adrenal glands begin producing more androgens like DHEA and androstenedione.

• Androgens: Steroid hormones, such as testosterone and DHEA, responsible for male characteristics and hair growth in both sexes.

• Estrogen: The main female sex hormone that regulates breast development and menstrual cycles.

• Growth Hormone (GH): A pituitary hormone that promotes body growth and metabolism but does not cause pubic hair development.

Lead Question - 2014
Pubarche is due to?
a) GH
b) Progesterone
c) Testosterone
d) Estrogen

Explanation: Pubarche, the appearance of pubic and axillary hair, occurs due to increased secretion of adrenal androgens such as dehydroepiandrosterone (DHEA) and androstenedione during adrenarche. These androgens are converted peripherally to testosterone, which stimulates hair follicle growth. Therefore, the correct answer is Testosterone.

1. The onset of adrenarche occurs at approximately what age?
a) 2–4 years
b) 5–7 years
c) 8–10 years
d) 12–14 years

Explanation: Adrenarche begins around 5–7 years of age, preceding puberty. During this period, the adrenal cortex (zona reticularis) matures and begins secreting higher levels of DHEA and androstenedione, leading to pubarche and other androgenic effects before gonadal activation.

2. Which adrenal zone is responsible for androgen production leading to pubarche?
a) Zona glomerulosa
b) Zona fasciculata
c) Zona reticularis
d) Zona pellucida

Explanation: The zona reticularis of the adrenal cortex secretes weak androgens like DHEA and androstenedione. These androgens are responsible for the development of pubic and axillary hair, marking the event known as pubarche. Hence, the correct answer is zona reticularis.

3. In girls, which event occurs first during puberty?
a) Pubarche
b) Thelarche
c) Menarche
d) Growth spurt

Explanation: Thelarche (breast development) usually occurs first, followed by pubarche, growth spurt, and finally menarche. Thelarche is due to estrogen effects, whereas pubarche is androgen-mediated. Hence, the earliest event is thelarche.

4. Pubarche occurs due to increased secretion of?
a) FSH
b) LH
c) DHEA
d) Prolactin

Explanation: The adrenal androgen DHEA (dehydroepiandrosterone) is primarily responsible for the appearance of pubic and axillary hair. Its secretion increases during adrenarche, preceding gonadal activation, and stimulates hair follicle maturation and sebaceous gland activity.

5. A 10-year-old girl presents with early pubic hair but no breast development. Likely diagnosis?
a) True precocious puberty
b) Premature adrenarche
c) Gonadal tumor
d) Central hypothyroidism

Explanation: Early appearance of pubic hair without other secondary sexual features indicates premature adrenarche. It results from early adrenal androgen secretion without activation of the hypothalamic-pituitary-gonadal axis. It is usually benign and self-limiting.

6. Which hormone does not contribute directly to pubarche?
a) Testosterone
b) DHEA
c) Estrogen
d) Androstenedione

Explanation: Estrogen primarily regulates female reproductive tissues and breast development but does not cause hair growth. Pubarche depends on adrenal androgens like testosterone, DHEA, and androstenedione. Hence, estrogen is not directly involved in pubic hair development.

7. In males, pubarche coincides with which event?
a) Voice deepening
b) Spermarche
c) Penile enlargement
d) Facial hair development

Explanation: In males, pubarche coincides with penile enlargement due to rising androgen levels. Facial hair and voice deepening occur later. Hence, penile enlargement typically occurs concurrently with pubic hair development during puberty.

8. Which of the following is true about adrenarche and gonadarche?
a) Adrenarche follows gonadarche
b) Both start simultaneously
c) Adrenarche precedes gonadarche
d) They are unrelated processes

Explanation: Adrenarche precedes gonadarche. Adrenarche involves adrenal androgen secretion, while gonadarche marks gonadal hormone activation (testosterone, estrogen). Although independent, both processes overlap during puberty and contribute to secondary sexual characteristics.

9. A 13-year-old boy with delayed puberty has low DHEA and low LH. The defect is most likely in?
a) Testes
b) Adrenal cortex
c) Hypothalamus
d) Pituitary gland

Explanation: Low levels of both DHEA (adrenal androgen) and LH (pituitary hormone) suggest a hypothalamic defect leading to decreased GnRH secretion. This causes underactivity of both adrenal and gonadal axes, resulting in delayed puberty.

10. Which enzyme is essential for androgen synthesis during adrenarche?
a) 21-hydroxylase
b) 11β-hydroxylase
c) 17,20-lyase
d) Aromatase

Explanation: The enzyme 17,20-lyase catalyzes the conversion of pregnenolone and progesterone into DHEA and androstenedione, which are key androgens responsible for pubarche. Deficiency of this enzyme leads to reduced androgen synthesis and delayed onset of secondary hair growth.

Topic: Puberty and Reproductive Hormones; Subtopic: Hormonal Regulation of Puberty

Keyword Definitions:

• Puberty: The transitional phase during which sexual maturity is achieved, marked by the development of secondary sexual characteristics and reproductive capability.

• Leptin: A hormone from adipose tissue that signals the hypothalamus to initiate puberty once sufficient body fat is accumulated.

• LH (Luteinizing Hormone): A pituitary hormone that stimulates testosterone production in males and ovulation in females.

• Testosterone: The primary male sex hormone responsible for male secondary sexual traits and spermatogenesis.

• GnRH (Gonadotropin-Releasing Hormone): A hypothalamic hormone that triggers LH and FSH secretion to start puberty.

Lead Question - 2014
Hormones required during puberty?
a) LH
b) Testosterone
c) Leptin
d) All of the above

Explanation: Puberty is regulated by a coordinated rise in GnRH, LH, FSH, sex steroids, and leptin. LH and FSH stimulate gonadal maturation, while testosterone and estrogen induce secondary sexual traits. Leptin, secreted by fat cells, signals adequate energy stores to initiate reproductive maturation. Thus, the correct answer is All of the above.

1. The first hormonal change during puberty is the increased secretion of?
a) LH
b) FSH
c) GnRH
d) Estrogen

Explanation: Puberty begins with increased pulsatile secretion of GnRH from the hypothalamus. This stimulates LH and FSH release, activating gonadal steroidogenesis. GnRH pulses are more frequent during sleep initially, marking the onset of puberty. Hence, the correct answer is GnRH.

2. Which of the following is the earliest sign of puberty in girls?
a) Menarche
b) Thelarche
c) Pubarche
d) Growth spurt

Explanation: The earliest sign of puberty in girls is thelarche (breast development) due to estrogen secretion stimulated by FSH. Menarche occurs later as ovulatory cycles establish. Pubarche and growth spurts follow in sequence during normal pubertal progression.

3. In boys, puberty is marked by increased secretion of?
a) Progesterone
b) Testosterone
c) Estrogen
d) LH only

Explanation: Puberty in boys begins with a rise in LH stimulating Leydig cells to produce testosterone. This hormone induces spermatogenesis, deepens the voice, and promotes muscle growth. Hence, testosterone is the primary hormone responsible for male pubertal changes.

4. Leptin acts primarily on which structure to initiate puberty?
a) Pituitary gland
b) Adrenal cortex
c) Hypothalamus
d) Thyroid gland

Explanation: Leptin acts on the hypothalamus to enhance GnRH secretion. It signals adequate energy reserves to begin reproductive function. Low leptin levels in undernutrition delay puberty, highlighting its role as a metabolic gatekeeper of sexual maturation.

5. A 14-year-old boy shows delayed puberty and low testosterone with high LH. Likely cause?
a) Pituitary defect
b) Testicular failure
c) Hypothalamic defect
d) Adrenal hyperplasia

Explanation: High LH with low testosterone indicates primary testicular failure (hypergonadotropic hypogonadism). The pituitary tries to compensate by secreting more LH, but the testes fail to respond, delaying puberty. The correct answer is testicular failure.

6. Which of the following hormones rises first during female puberty?
a) LH
b) FSH
c) Estrogen
d) Progesterone

Explanation: In girls, FSH secretion rises first, stimulating follicle growth and estrogen production. LH surges later to trigger ovulation. Estrogen then leads to breast development and uterine growth. Hence, FSH is the earliest to rise during puberty.

7. A 12-year-old girl with normal height but absent breast development and low estrogen likely has deficiency of?
a) GnRH
b) FSH
c) LH
d) All of the above

Explanation: The absence of breast development and low estrogen with normal growth suggests hypogonadotropic hypogonadism, often due to GnRH deficiency. Without GnRH, LH and FSH are not released, preventing estrogen production and secondary sexual traits.

8. Puberty may be delayed in anorexic individuals due to low levels of?
a) Cortisol
b) Leptin
c) Insulin
d) Growth hormone

Explanation: Anorexia leads to decreased adipose tissue and reduced leptin levels. Leptin deficiency inhibits GnRH release, delaying puberty. Hence, delayed puberty in anorexia is primarily due to low leptin levels affecting hypothalamic-pituitary-gonadal axis activation.

9. The main cause of precocious puberty in girls is?
a) Pituitary tumor
b) Hypothalamic activation
c) Ovarian failure
d) Adrenal insufficiency

Explanation: True precocious puberty is usually due to premature activation of the hypothalamic-pituitary-gonadal axis (central type). This leads to early GnRH, LH, and FSH secretion. Hence, the cause is hypothalamic activation.

10. In males, the hormone responsible for spermatogenesis initiation during puberty is?
a) LH
b) FSH
c) Prolactin
d) Testosterone

Explanation: FSH acts on Sertoli cells to initiate spermatogenesis during puberty. LH supports Leydig cells to produce testosterone, which also facilitates sperm maturation. Thus, FSH plays a crucial role in initiating spermatogenesis during male puberty.

Topic: Female Reproductive Hormones; Subtopic: Estrogen Receptors and their Distribution

Keyword Definitions:
• Estrogen: A steroid hormone produced mainly by the ovaries responsible for secondary sexual characteristics and reproductive cycle regulation.
• Estrogen Receptors (ER): Proteins that mediate estrogen’s effects; two main types are ER-α and ER-β.
• ER-β (Estrogen Beta Receptors): Receptor subtype found predominantly in ovary, vascular endothelium, and certain brain regions.
• Ovary: The female gonad producing ova and hormones such as estrogen and progesterone.

Lead Question - 2014
Estrogen Beta receptors are found on:
a) Uterus
b) Blood vessels
c) Ovary
d) Vagina

Explanation: The correct answer is (c) Ovary. Estrogen β receptors (ER-β) are expressed in high concentrations in the ovary, prostate, lungs, and cardiovascular tissues. They modulate gene transcription distinct from ER-α, influencing follicular growth, vascular tone, and cellular differentiation. ER-α is abundant in the uterus and breast, while ER-β plays a key role in ovarian physiology and vascular health.

1) Which type of estrogen receptor is predominantly found in the uterus?
a) ER-α
b) ER-β
c) Both equally
d) None
Explanation: The correct answer is (a) ER-α. Estrogen receptor alpha (ER-α) is mainly expressed in the uterus, mammary glands, and liver. It regulates gene transcription that promotes uterine growth and endometrial proliferation. In contrast, ER-β dominates in ovaries, brain, and vascular tissues, mediating different cellular functions including anti-proliferative effects.

2) ER-β receptors in ovaries primarily regulate which of the following?
a) Ovum maturation
b) LH secretion
c) Endometrial thickening
d) Progesterone synthesis
Explanation: The correct answer is (a) Ovum maturation. ER-β is crucial for follicular development, ovum maturation, and prevention of granulosa cell apoptosis. It modulates follicle-stimulating hormone (FSH) signaling pathways to ensure proper oocyte growth and release during ovulation. Thus, ER-β is central to reproductive function in the ovary.

3) (Clinical) Deficiency of ER-β receptors can cause?
a) Anovulation
b) Amenorrhea
c) Premature menopause
d) Increased fertility
Explanation: The correct answer is (a) Anovulation. ER-β deficiency disrupts follicular development and ovum maturation, leading to anovulatory cycles. Clinically, this presents as infertility or irregular menses. Animal models lacking ER-β show impaired folliculogenesis despite normal ER-α expression, emphasizing its specific role in ovarian physiology.

4) Which organ expresses both ER-α and ER-β equally?
a) Brain
b) Uterus
c) Kidney
d) Thyroid
Explanation: The correct answer is (a) Brain. Both estrogen receptor subtypes coexist in the hypothalamus and hippocampus. ER-α modulates reproductive hormone regulation, while ER-β contributes to neuroprotection, synaptic plasticity, and cognitive functions. Together, they influence mood regulation and sexual behavior in both sexes.

5) (Clinical) In postmenopausal women, ER-β activation in blood vessels helps by?
a) Increasing blood pressure
b) Reducing endothelial damage
c) Causing thrombosis
d) Reducing nitric oxide release
Explanation: The correct answer is (b) Reducing endothelial damage. Estrogen acting on ER-β receptors enhances nitric oxide release, improving vasodilation and vascular health. Postmenopausal estrogen loss increases cardiovascular risk due to reduced ER-β-mediated protection. Thus, selective ER-β modulators are being explored for cardiovascular benefits without stimulating uterine proliferation.

6) Estrogen receptor alpha (ER-α) gene is located on which chromosome?
a) Chromosome 4
b) Chromosome 6
c) Chromosome 14
d) Chromosome 1
Explanation: The correct answer is (d) Chromosome 1. The gene for ER-α (ESR1) resides on chromosome 1, while ER-β (ESR2) is located on chromosome 14. These distinct genetic origins explain their different tissue distributions and functional roles in estrogen signaling and target gene activation.

7) (Clinical) A woman on selective estrogen receptor modulators (SERMs) has uterine proliferation but reduced breast risk. Which receptor subtype is likely targeted?
a) ER-α agonist, ER-β antagonist
b) ER-α antagonist, ER-β agonist
c) ER-β antagonist
d) ER-α agonist only
Explanation: The correct answer is (b) ER-α antagonist, ER-β agonist. SERMs like raloxifene act as ER-β agonists (beneficial for bones and vessels) and ER-α antagonists (reducing uterine and breast proliferation), achieving tissue-selective estrogenic effects useful in osteoporosis and breast cancer prevention.

8) Estrogen receptors belong to which receptor class?
a) G-protein coupled receptor
b) Ligand-gated ion channel
c) Nuclear receptor
d) Enzyme-linked receptor
Explanation: The correct answer is (c) Nuclear receptor. Estrogen receptors are nuclear hormone receptors that act as transcription factors. Upon binding estrogen, they form dimers, bind estrogen response elements (ERE) on DNA, and regulate gene expression involved in reproduction, metabolism, and growth regulation.

9) Which estrogen type has the highest affinity for both ER-α and ER-β?
a) Estrone
b) Estriol
c) Estradiol
d) Ethinyl estradiol
Explanation: The correct answer is (c) Estradiol. Estradiol (E2) is the most potent natural estrogen with high affinity for both receptor subtypes. It plays a vital role in maintaining reproductive function, bone density, and cardiovascular health in premenopausal women through receptor-mediated genomic and non-genomic effects.

10) (Clinical) ER-β agonists are being developed for the treatment of?
a) Endometrial carcinoma
b) Osteoporosis
c) Hypertension
d) Hypothyroidism
Explanation: The correct answer is (b) Osteoporosis. ER-β agonists enhance bone formation and reduce bone resorption without stimulating uterine or breast tissue. By promoting osteoblastic activity and inhibiting osteoclasts, they mimic estrogen’s beneficial skeletal effects while minimizing risks associated with traditional hormone replacement therapy.

Topic: Male Reproductive Physiology; Subtopic: Sperm Capacitation and Fertilization

Keyword Definitions:
• Capacitation: The physiological process that sperm undergo in the female reproductive tract to gain the ability to fertilize an ovum.
• Acrosome: A cap-like vesicle on the sperm head containing enzymes that help penetrate the ovum.
• Calcium permeability: Calcium influx is essential for sperm motility and acrosomal reaction.
• Cholesterol removal: Cholesterol efflux from the sperm membrane enhances its fluidity during capacitation.

Lead Question - 2014
Following changes are seen during capacitation of sperms except?
a) Increased permeability to calcium
b) Decreased permeability to calcium
c) Removal of cholesterol from acrosome
d) Increased motility

Explanation: The correct answer is (b) Decreased permeability to calcium. During capacitation, spermatozoa undergo biochemical modifications including increased permeability to calcium ions, removal of cholesterol from the plasma membrane, and enhanced motility. These changes prepare sperm for the acrosomal reaction necessary for fertilization. Decreased calcium permeability would inhibit capacitation and prevent fertilization.

1) Which enzyme helps sperm to penetrate the zona pellucida?
a) Hyaluronidase
b) Acrosin
c) Lipase
d) Trypsin
Explanation: The correct answer is (b) Acrosin. Acrosin is a proteolytic enzyme released from the acrosome of the sperm during the acrosomal reaction. It helps digest the glycoprotein matrix of the zona pellucida, facilitating sperm entry into the oocyte. This reaction occurs after capacitation, enabling successful fertilization in the ampulla of the fallopian tube.

2) Where does sperm capacitation occur in the female reproductive tract?
a) Uterus
b) Cervix
c) Vagina
d) Fallopian tube
Explanation: The correct answer is (d) Fallopian tube. Capacitation mainly occurs in the ampullary region of the fallopian tube, where sperm are exposed to female tract secretions. These secretions remove surface glycoproteins and cholesterol, enhancing membrane fluidity. This environment activates sperm motility and prepares them for the acrosome reaction necessary for fertilization.

3) Capacitation leads to which of the following outcomes?
a) Reduced sperm motility
b) Acrosome stabilization
c) Hyperactivated motility
d) DNA fragmentation
Explanation: The correct answer is (c) Hyperactivated motility. Capacitation increases sperm motility due to calcium influx and cAMP signaling. This hyperactivation enables sperm to move vigorously and penetrate the cumulus oophorus and zona pellucida. The acrosomal reaction then allows sperm to fuse with the oocyte membrane, leading to fertilization.

4) (Clinical) A male patient with defective sperm capacitation may have infertility due to failure of?
a) Sperm motility
b) Acrosome reaction
c) Testosterone production
d) Spermatogenesis
Explanation: The correct answer is (b) Acrosome reaction. Defective capacitation prevents sperm from undergoing acrosomal reaction, thereby inhibiting penetration of the zona pellucida. This leads to fertilization failure. Capacitation failure may result from abnormalities in seminal plasma proteins or impaired membrane cholesterol efflux affecting calcium ion channels.

5) What is the time duration required for human sperm capacitation?
a) 15 minutes
b) 1 hour
c) 6–8 hours
d) 24 hours
Explanation: The correct answer is (c) 6–8 hours. Human sperm typically require 6–8 hours within the female genital tract to undergo capacitation. During this period, the sperm membranes undergo enzymatic and ionic modifications. These changes are essential for preparing sperm for the acrosome reaction and subsequent fertilization.

6) (Clinical) A couple with normal sperm count but failure of fertilization in IVF may have a defect in?
a) Sperm capacitation
b) Sperm motility
c) Zona pellucida
d) Endometrium
Explanation: The correct answer is (a) Sperm capacitation. Even with normal count and motility, defective capacitation prevents acrosome reaction and sperm-egg binding. In IVF labs, capacitation can be induced artificially using media containing albumin and calcium ions. Proper capacitation ensures successful zona penetration and fertilization.

7) Which ion is most essential for the process of sperm capacitation?
a) Sodium
b) Potassium
c) Calcium
d) Magnesium
Explanation: The correct answer is (c) Calcium. Calcium influx triggers biochemical signaling pathways that regulate motility and acrosome exocytosis. Calcium channels in the sperm plasma membrane become more active during capacitation, contributing to increased motility and preparation for zona pellucida penetration.

8) During capacitation, sperm membrane loses?
a) Cholesterol
b) Calcium
c) Sodium
d) Protein
Explanation: The correct answer is (a) Cholesterol. The removal of cholesterol and glycoproteins from the sperm membrane enhances membrane fluidity, making it responsive to signals from the oocyte’s zona pellucida. This step is critical for successful fertilization and membrane fusion between gametes.

9) (Clinical) A patient undergoing IVF is given heparin in the capacitation medium because it?
a) Activates calcium channels
b) Removes cholesterol from sperm membrane
c) Inhibits sperm motility
d) Prevents acrosomal damage
Explanation: The correct answer is (b) Removes cholesterol from sperm membrane. Heparin is used in vitro to induce sperm capacitation by promoting cholesterol efflux. This increases membrane fluidity, enabling calcium influx and hyperactivation. Such preparation mimics the natural capacitation environment of the female reproductive tract.

10) (Clinical) Failure of zona pellucida penetration by sperm indicates a defect in?
a) Acrosin release
b) Flagellar motion
c) Sertoli cells
d) Leydig cells
Explanation: The correct answer is (a) Acrosin release. Acrosin is vital for enzymatic digestion of the zona pellucida. Its absence or defective release prevents sperm penetration and fertilization. This can occur due to abnormal capacitation or defective acrosomal enzymes, commonly leading to infertility.

Topic: Female Reproductive Physiology; Subtopic: Graafian Follicle and Ovum Maturation

Keyword Definitions:
• Graafian follicle: The mature ovarian follicle containing the secondary oocyte ready for ovulation.
• Oocyte: The female gamete that undergoes meiotic division to form the ovum.
• Cumulus oophorus: A cluster of granulosa cells surrounding the oocyte that nourishes and supports it.
• Luteal cells: Cells formed from granulosa and theca after ovulation that secrete progesterone.

Lead Question - 2014
Cells which surround the oocyst in graafian follicle are called?
a) Discus proligerus
b) Cumulus oophoricus
c) Luteal cells
d) Villus cells

Explanation: The correct answer is (b) Cumulus oophoricus. These granulosa cells form a protective mass around the oocyte, connecting it to the follicular wall via the discus proligerus. They supply nutrients and signaling molecules essential for oocyte maturation and release during ovulation. The luteal cells form later after ovulation.

1) The hormone responsible for follicular growth is?
a) LH
b) FSH
c) Estrogen
d) Progesterone
Explanation: The correct answer is (b) FSH. Follicle-stimulating hormone stimulates the growth of ovarian follicles and the proliferation of granulosa cells. FSH also promotes estrogen secretion by granulosa cells. Its surge, along with LH, leads to follicle maturation before ovulation. FSH is secreted by the anterior pituitary gland.

2) Ovulation is triggered by a surge in which hormone?
a) LH
b) FSH
c) Progesterone
d) Oxytocin
Explanation: The correct answer is (a) LH. The mid-cycle surge of luteinizing hormone causes rupture of the mature Graafian follicle, releasing the secondary oocyte. LH acts on the follicular wall, increasing proteolytic enzyme activity. It also transforms granulosa cells into luteal cells after ovulation for progesterone secretion.

3) The corpus luteum primarily secretes?
a) Estrogen
b) LH
c) Progesterone
d) FSH
Explanation: The correct answer is (c) Progesterone. Corpus luteum forms from the remnants of the ruptured Graafian follicle and secretes progesterone, which prepares the endometrium for implantation. If fertilization doesn’t occur, it degenerates into corpus albicans, leading to decreased hormone levels and menstruation.

4) Theca interna cells of Graafian follicle produce?
a) Estrogen
b) Progesterone
c) LH
d) FSH
Explanation: The correct answer is (a) Estrogen. Theca interna cells synthesize androgens under LH stimulation. These androgens are converted to estrogen by granulosa cells through the enzyme aromatase. Estrogen promotes proliferation of the endometrium and feedback regulation of gonadotropin release.

5) Which of the following cells are derived from granulosa cells after ovulation?
a) Luteal cells
b) Theca externa
c) Germ cells
d) Stromal cells
Explanation: The correct answer is (a) Luteal cells. After ovulation, granulosa and theca cells luteinize to form luteal cells in the corpus luteum. These cells secrete progesterone and small amounts of estrogen, maintaining the endometrium for potential implantation and early pregnancy support.

6) (Clinical) A woman with anovulatory cycles likely lacks a surge of which hormone?
a) FSH
b) LH
c) Estrogen
d) Progesterone
Explanation: The correct answer is (b) LH. The absence of LH surge prevents follicular rupture, causing anovulation. Such cycles are common in polycystic ovarian syndrome (PCOS), stress, or hormonal imbalance. Lack of progesterone due to no corpus luteum formation may lead to irregular menstrual bleeding.

7) (Clinical) In polycystic ovarian syndrome, which hormone is typically elevated?
a) LH
b) FSH
c) Estrogen
d) Prolactin
Explanation: The correct answer is (a) LH. PCOS is characterized by an increased LH:FSH ratio, anovulation, and hyperandrogenism. Excess LH stimulates theca cells to produce androgens, while insufficient FSH prevents normal follicular maturation. This leads to multiple immature cysts in ovaries and infertility.

8) (Clinical) Luteal phase defect results in?
a) Early ovulation
b) Infertility
c) Multiple ovulations
d) Increased FSH
Explanation: The correct answer is (b) Infertility. In luteal phase defect, corpus luteum fails to produce adequate progesterone, causing poor endometrial development. This results in failed implantation or early miscarriage. Hormonal imbalance, stress, or inadequate LH support may contribute to this defect.

9) (Clinical) A patient with excessive estrogen but no ovulation likely has?
a) Follicular cyst
b) Corpus luteum cyst
c) Endometrial polyp
d) Luteal cyst
Explanation: The correct answer is (a) Follicular cyst. Follicular cysts form when Graafian follicles fail to rupture and continue growing, producing estrogen. This condition can cause menstrual irregularities, mild pain, and endometrial hyperplasia due to prolonged estrogen exposure.

10) (Clinical) Absence of corpus luteum indicates failure of?
a) Ovulation
b) Fertilization
c) Implantation
d) Menstruation
Explanation: The correct answer is (a) Ovulation. Corpus luteum develops only after ovulation. Its absence suggests no follicular rupture, typical in anovulatory cycles. This leads to absence of progesterone and failure of endometrial secretory changes, contributing to infertility and abnormal uterine bleeding.

Topic: Fertilization and Early Development; Subtopic: Blastocyst Formation and Hatching

Keyword Definitions:

• Blastocyst: A hollow ball of cells formed about 5–6 days after fertilization, consisting of the inner cell mass and trophoblast.

• Zona pellucida: A glycoprotein shell around the zygote that protects it until implantation.

• Hatching: The process by which the blastocyst breaks free from the zona pellucida before implantation.

• Fertilization: Union of sperm and ovum in the fallopian tube forming a zygote.

• Implantation: Attachment of the blastocyst to the uterine endometrium.

• Cleavage: Rapid mitotic divisions of the zygote without cell growth.

• Trophoblast: Outer layer of cells in the blastocyst that forms part of the placenta.

Lead Question (2014):
Blastocyst comes out on which day after fertilization?
a) 4-7 days
b) 10-12 days
c) 12-15 days
d) 15-20 days

Explanation:
The blastocyst emerges from the zona pellucida around the 5th to 6th day after fertilization, a process known as hatching. This allows it to implant into the endometrial lining. Hatching is crucial for implantation as the zona pellucida prevents premature adhesion. The correct answer is (a) 4–7 days.

1) The blastocyst stage in humans occurs around which day after fertilization?
a) Day 2
b) Day 3
c) Day 5
d) Day 8

After fertilization, the zygote undergoes cleavage to form a morula by day 3 and then a blastocyst by day 5. The blastocyst then moves toward the uterus and prepares for implantation. This transformation marks the start of embryonic development. Hence, the correct answer is (c) Day 5.

2) Clinical case: A 30-year-old woman undergoing IVF has embryos transferred on day 5. What stage are they at?
a) Zygote
b) Morula
c) Blastocyst
d) Gastrula

In in vitro fertilization (IVF), embryos are commonly transferred on day 5 when they reach the blastocyst stage. This stage offers higher implantation potential due to cellular differentiation. Blastocyst transfer synchronizes better with endometrial receptivity. Hence, the correct answer is (c) Blastocyst.

3) Zona hatching of the blastocyst is essential for:
a) Cleavage
b) Implantation
c) Gastrulation
d) Placenta formation

The blastocyst must break free from the zona pellucida to implant into the uterus. This process, known as zona hatching, occurs around the 5th–6th day post-fertilization and allows trophoblast cells to attach to the endometrium. Hence, the correct answer is (b) Implantation.

4) Clinical case: A patient with thin endometrium after IVF shows failure of implantation. What could be the likely reason?
a) Early hatching
b) Late hatching
c) Early cleavage
d) Multiple zygotes

If implantation fails due to delayed blastocyst hatching or endometrial asynchrony, the embryo cannot adhere to the uterine wall. Late hatching delays implantation timing and reduces pregnancy chances. Therefore, the correct answer is (b) Late hatching.

5) Which layer of the blastocyst forms the placenta?
a) Inner cell mass
b) Trophoblast
c) Zona pellucida
d) Blastocoel

The trophoblast forms the outer layer of the blastocyst and gives rise to the placenta and extraembryonic membranes. It provides nutrients and supports the embryo. The inner cell mass develops into the embryo proper. Hence, the correct answer is (b) Trophoblast.

6) The fluid-filled cavity within the blastocyst is called:
a) Morula
b) Amnion
c) Blastocoel
d) Yolk sac

The blastocoel is a fluid-filled cavity within the blastocyst that forms as the morula differentiates. It separates the inner cell mass from the trophoblast and helps expand the blastocyst before implantation. Thus, the correct answer is (c) Blastocoel.

7) Clinical case: A woman with blocked fallopian tubes is unable to conceive naturally. Which process is most affected?
a) Fertilization and zygote transport
b) Ovulation
c) Blastocyst hatching
d) Endometrial development

Blocked fallopian tubes prevent the sperm from reaching the ovum and hinder zygote transport to the uterus. Therefore, both fertilization and zygote transport are affected. Implantation cannot occur as the blastocyst never reaches the uterus. Hence, the correct answer is (a) Fertilization and zygote transport.

8) The morula contains approximately how many cells?
a) 4
b) 8
c) 16
d) 32

The morula is a 16-cell stage embryo formed by cleavage of the zygote around day 3 after fertilization. It resembles a mulberry in appearance and precedes the blastocyst stage. The correct answer is (c) 16 cells.

9) Which event marks the transition from morula to blastocyst?
a) Formation of blastocoel
b) Zona hardening
c) Cleavage
d) Fertilization

The formation of the blastocoel cavity marks the transition from morula to blastocyst. Fluid accumulates between cells, creating a cavity that differentiates the trophoblast and inner cell mass. Hence, the correct answer is (a) Formation of blastocoel.

10) Clinical case: A 35-year-old woman conceives after IVF. Ultrasound on day 7 post-transfer shows no implantation. What is the likely reason?
a) Early hatching
b) Failed hatching
c) Normal delay
d) Progesterone excess

In IVF, if no implantation is seen after day 7, the most probable cause is failed hatching of the blastocyst. Without shedding the zona pellucida, it cannot attach to the uterine wall. Assisted hatching techniques are used to improve success rates. Hence, the correct answer is (b) Failed hatching.

Topic: Fertilization and Implantation; Subtopic: Day of Implantation in Menstrual Cycle

Keyword Definitions:

• Menstrual Cycle: A 28-day cycle involving hormonal changes preparing the uterus for pregnancy.

• Ovulation: Release of a mature ovum from the ovary around the 14th day of the cycle.

• Fertilization: Fusion of sperm and ovum forming a zygote in the fallopian tube.

• Blastocyst: A multicellular structure formed after several zygotic divisions before implantation.

• Implantation: Process where the blastocyst attaches to the uterine endometrium.

• Endometrium: Inner uterine lining that becomes secretory under progesterone influence for implantation.

• Corpus luteum: Temporary endocrine structure secreting progesterone to support pregnancy.

Lead Question (2014):
Implantation occurs on which menstrual cycle day?
a) 5-7 days
b) 20-22 days
c) 14-18 days
d) 26-28 days

Explanation:
Implantation usually occurs around the 20th to 22nd day of the menstrual cycle, approximately 6 to 7 days after ovulation and fertilization. The endometrium is in the secretory phase, rich in glycogen and blood supply, making it receptive for implantation. Progesterone secreted by the corpus luteum maintains this environment. Thus, the correct answer is (b) 20-22 days.

1) Fertilization occurs on which day of the menstrual cycle?
a) 10th day
b) 14th day
c) 20th day
d) 26th day

In a 28-day menstrual cycle, ovulation happens on the 14th day, and fertilization usually takes place within 24 hours in the fallopian tube. The sperm remains viable for about 72 hours, making this the fertile window. Hence, the correct answer is (b) 14th day.

2) The luteal phase of the menstrual cycle lasts for approximately:
a) 5 days
b) 10 days
c) 14 days
d) 20 days

The luteal phase follows ovulation and lasts about 14 days. During this phase, the corpus luteum secretes progesterone, converting the endometrium into a secretory lining ready for implantation. If fertilization doesn’t occur, the corpus luteum degenerates, leading to menstruation. Thus, the correct answer is (c) 14 days.

3) Clinical case: A woman with luteal phase defect is unable to conceive. The probable cause is:
a) Low progesterone
b) High estrogen
c) Low FSH
d) High LH

A luteal phase defect leads to inadequate progesterone secretion from the corpus luteum, resulting in an endometrium not properly prepared for implantation. This hormonal imbalance causes infertility or early miscarriage. Therefore, the correct answer is (a) Low progesterone.

4) Clinical case: Implantation occurs on day 25 of the cycle. Which statement is correct?
a) Normal implantation
b) Delayed implantation
c) Early implantation
d) Abnormal implantation

Implantation occurring beyond day 22 of the menstrual cycle is considered delayed implantation. It may happen due to late ovulation or slow zygote transport. Such delay can affect endometrial receptivity, reducing chances of pregnancy. Hence, the correct answer is (b) Delayed implantation.

5) The “implantation window” refers to:
a) Day 1-5
b) Day 14-16
c) Day 20-24
d) Day 26-28

The implantation window is the limited period when the endometrium is receptive to the blastocyst, typically from day 20 to day 24 of the menstrual cycle. Progesterone and estrogen balance is crucial during this time for successful implantation. Thus, the correct answer is (c) Day 20-24.

6) Clinical case: A woman undergoes IVF, and embryo transfer is done on day 5 post-ovulation. Implantation is expected around:
a) Day 10
b) Day 14
c) Day 19-21
d) Day 26

In IVF, embryo transfer usually occurs on day 5 post-ovulation (blastocyst stage). Implantation follows about 5 to 6 days later, coinciding with day 19 to 21 of a natural cycle. Synchronization of endometrial receptivity is crucial for success. Thus, the correct answer is (c) Day 19-21.

7) Which hormone prepares the endometrium for implantation?
a) LH
b) Estrogen
c) Progesterone
d) FSH

The hormone responsible for preparing the endometrium for implantation is progesterone. It transforms the proliferative endometrium into a secretory one, rich in nutrients for the developing blastocyst. It also suppresses uterine contractions, allowing attachment of the embryo. Hence, the correct answer is (c) Progesterone.

8) Clinical case: In ectopic pregnancy, implantation occurs most commonly at:
a) Cervix
b) Ovary
c) Fallopian tube
d) Uterus

In ectopic pregnancy, implantation occurs outside the uterine cavity. The most common site is the ampulla of the fallopian tube. It results from impaired transport of the zygote and may cause rupture and internal bleeding. Hence, the correct answer is (c) Fallopian tube.

9) Implantation in the uterus is facilitated by which layer of the endometrium?
a) Basalis
b) Functionalis
c) Compact layer
d) Spongy layer

Implantation occurs in the compact layer of the functionalis part of the endometrium, where trophoblast cells invade maternal tissues. The spongy layer contributes to early placental development. The basal layer regenerates after menstruation. Therefore, the correct answer is (c) Compact layer.

10) Clinical case: If implantation fails repeatedly, which diagnostic test is useful to evaluate endometrial receptivity?
a) AMH test
b) Endometrial biopsy
c) FSH level
d) Karyotyping

An endometrial biopsy helps evaluate whether the endometrium has undergone proper secretory transformation, indicating its receptivity for implantation. It detects progesterone deficiency or luteal phase defects. Therefore, for recurrent implantation failure, the correct test is (b) Endometrial biopsy.

Topic: Fertilization and Implantation; Subtopic: Timing and Process of Implantation

Keyword Definitions:

• Fertilization: Fusion of sperm and ovum to form a zygote.

• Zygote: The first cell formed after fertilization containing diploid chromosomes.

• Blastocyst: A structure formed after multiple divisions of the zygote before implantation.

• Implantation: The attachment of the blastocyst to the uterine wall.

• Endometrium: The inner lining of the uterus where implantation occurs.

• Luteal phase: Phase after ovulation characterized by progesterone secretion from corpus luteum.

Lead Question (2014):
Implantation occurs at ?
a) 2-3 days
b) 6-7 days
c) 15-20 days
d) 20-25 days

Explanation:
Implantation of the blastocyst normally occurs about 6-7 days after fertilization. The zygote travels through the fallopian tube for nearly 3-4 days before entering the uterus and developing into a blastocyst. It then attaches to the endometrium, facilitated by progesterone. Thus, the correct answer is (b) 6-7 days.

1) Site of fertilization in humans is:
a) Uterus
b) Vagina
c) Ampulla of fallopian tube
d) Cervix

Fertilization in humans occurs in the ampulla of the fallopian tube, which provides an ideal environment for the union of sperm and ovum. The fertilized ovum then travels to the uterus for implantation after cleavage. Therefore, the correct answer is (c) Ampulla of fallopian tube.

2) Corpus luteum mainly secretes:
a) FSH
b) LH
c) Progesterone
d) Estrogen

The corpus luteum forms from the ruptured follicle after ovulation and secretes progesterone. This hormone maintains the endometrial lining suitable for implantation. If fertilization does not occur, the corpus luteum degenerates. Hence, the correct answer is (c) Progesterone.

3) Which hormone prevents menstruation after implantation?
a) LH
b) hCG
c) Estrogen
d) FSH

After implantation, the trophoblast secretes human chorionic gonadotropin (hCG), which maintains the corpus luteum and continuous progesterone secretion. This prevents menstruation and supports early pregnancy. Thus, the correct answer is (b) hCG.

4) Clinical case: A woman conceives, and implantation occurs on the posterior uterine wall. This position is:
a) Normal implantation
b) Ectopic pregnancy
c) Placenta previa
d) Cervical implantation

In normal pregnancies, implantation occurs on the posterior wall of the uterus. This location provides good vascularization for placental growth. Ectopic pregnancy occurs outside the uterus, commonly in fallopian tubes. Hence, the correct answer is (a) Normal implantation.

5) Ectopic implantation most commonly occurs in:
a) Cervix
b) Ovary
c) Ampulla of fallopian tube
d) Abdominal cavity

The most common site of ectopic pregnancy is the ampulla of the fallopian tube. This occurs when the zygote fails to move into the uterus due to blockage or damage. It can cause internal bleeding and is life-threatening if untreated. Hence, the correct answer is (c) Ampulla of fallopian tube.

6) Implantation is assisted mainly by:
a) Estrogen
b) Progesterone
c) LH
d) FSH

Progesterone, secreted by the corpus luteum, makes the endometrium secretory and receptive for implantation. Estrogen only helps in proliferation of endometrial lining but not implantation. Thus, the hormone mainly assisting implantation is (b) Progesterone.

7) Clinical case: A patient with defective corpus luteum fails to sustain pregnancy. The cause is:
a) Lack of progesterone
b) Lack of estrogen
c) Lack of LH
d) Lack of FSH

Failure of implantation or early pregnancy loss due to a defective corpus luteum is because of insufficient progesterone secretion. Progesterone maintains endometrial stability and supports embryonic growth. Therefore, the correct answer is (a) Lack of progesterone.

8) Implantation usually occurs in:
a) Isthmus of uterus
b) Posterior wall of uterus
c) Cervical canal
d) Fallopian tube

The blastocyst implants normally on the posterior wall of the uterus, near the fundus. This region has a rich blood supply, ensuring proper placental development and nutrition. Thus, the correct answer is (b) Posterior wall of uterus.

9) Clinical case: A woman shows implantation in the cervix. The condition is called:
a) Placenta previa
b) Cervical pregnancy
c) Tubal pregnancy
d) Interstitial pregnancy

Implantation in the cervical canal is known as cervical pregnancy, a type of ectopic implantation. It causes severe bleeding because of poor muscular support in the cervix. Hence, the correct answer is (b) Cervical pregnancy.

10) Clinical case: A zygote implants outside the uterus in the abdominal cavity. This type of pregnancy is:
a) Normal
b) Ectopic
c) Placenta accreta
d) Uterine pregnancy

Implantation occurring outside the uterus, such as in the fallopian tube or abdominal cavity, is termed an ectopic pregnancy. It cannot proceed normally and poses a serious risk to the mother. Therefore, the correct answer is (b) Ectopic.

Topic: Fertilization and Early Embryonic Development; Subtopic: Timing and Site of Fertilization

Keyword Definitions:
• Fertilization: Fusion of male and female gametes to form a zygote, marking the beginning of a new organism.
• Ovulation: Release of a mature ovum from the Graafian follicle into the fallopian tube.
• Ampulla: The widest part of the fallopian tube where fertilization usually occurs.
• Zygote: The first diploid cell formed after fusion of the sperm and ovum.

Lead Question - 2014
Fertilization takes place after how much time of ovulation?
a) 1–2 days
b) 5–6 days
c) 8–12 days
d) >12 days

Explanation: Fertilization typically occurs within 1–2 days after ovulation, usually in the ampulla of the fallopian tube. The ovum remains viable for about 24 hours after ovulation, while sperm can survive up to 72 hours in the female genital tract. Hence, fertilization occurs soon after ovulation. The correct answer is (a) 1–2 days.

1. Site of fertilization in the human female reproductive tract?
a) Isthmus
b) Ampulla
c) Infundibulum
d) Cervix
Explanation: Fertilization most commonly occurs in the ampulla of the fallopian tube, which provides the optimal environment for sperm-ovum interaction. The ampulla has ciliated epithelium aiding gamete movement and nutrient support. Therefore, the correct answer is (b) Ampulla.

2. Clinical: A woman has a blockage at the ampulla of her fallopian tube. What is the likely consequence?
a) No ovulation
b) No fertilization
c) No implantation
d) Multiple ovulations
Explanation: Blockage of the ampulla prevents the meeting of sperm and ovum, thereby preventing fertilization. Ovulation may still occur, but without fertilization, pregnancy cannot result. Hence, the correct answer is (b) No fertilization.

3. Fertilization normally occurs within how many hours after ovulation?
a) 6–12 hours
b) 12–24 hours
c) 36–48 hours
d) 72 hours
Explanation: Fertilization occurs within 12–24 hours after ovulation since the ovum remains viable for only one day. Sperm deposited earlier can survive in the female reproductive tract for about three days, ready for fertilization. Thus, the correct answer is (b) 12–24 hours.

4. Clinical: Fertilization occurring in the fallopian tube can abnormally result in?
a) Ectopic pregnancy
b) Hydatidiform mole
c) Blighted ovum
d) Molar pregnancy
Explanation: If the zygote implants within the fallopian tube instead of the uterus, it results in an ectopic pregnancy, a life-threatening condition requiring emergency treatment. It usually occurs in the ampulla or isthmus. Therefore, the correct answer is (a) Ectopic pregnancy.

5. Which enzyme in sperm aids in penetrating the zona pellucida during fertilization?
a) Hyaluronidase
b) Acrosin
c) Collagenase
d) Trypsin
Explanation: The enzyme acrosin from the acrosome of sperm facilitates penetration of the zona pellucida surrounding the ovum. Hyaluronidase helps disperse the corona radiata. Both are crucial for successful fertilization. The correct answer is (b) Acrosin.

6. Clinical: A 30-year-old woman has polyspermy. What does it lead to?
a) Normal fertilization
b) Triploid zygote
c) Monosomy
d) Blastocyst formation
Explanation: Polyspermy is the entry of multiple sperms into one ovum, leading to an abnormal triploid zygote (3n) that is nonviable. The ovum normally prevents this by cortical granule release that hardens the zona pellucida. Hence, the correct answer is (b) Triploid zygote.

7. Which event follows immediately after fertilization?
a) Cleavage
b) Implantation
c) Gastrulation
d) Neurulation
Explanation: After fertilization, the zygote undergoes rapid mitotic divisions known as cleavage to form a morula and then a blastocyst before implantation. Hence, the correct answer is (a) Cleavage.

8. Clinical: Fertilization usually occurs in which part of the fallopian tube in a normal pregnancy?
a) Isthmus
b) Ampullary-isthmic junction
c) Infundibulum
d) Fimbriae
Explanation: Fertilization most commonly occurs in the ampullary-isthmic junction, where both sperm and ovum meet. It provides the right environment for capacitation and fertilization. Therefore, the correct answer is (b) Ampullary-isthmic junction.

9. Clinical: In in-vitro fertilization, when are oocytes usually retrieved post-hCG injection?
a) 6 hours
b) 12 hours
c) 34–36 hours
d) 72 hours
Explanation: Oocyte retrieval in IVF is done approximately 34–36 hours after hCG injection, just before ovulation occurs, ensuring mature oocytes are collected for fertilization. Hence, the correct answer is (c) 34–36 hours.

10. What happens to the ovum if fertilization does not occur?
a) It divides to form a zygote
b) It degenerates within 24 hours
c) It implants in the uterus
d) It undergoes mitosis
Explanation: The ovum survives only for about 24 hours after ovulation. If fertilization does not occur, it degenerates in the fallopian tube, and menstruation follows due to falling progesterone levels. Hence, the correct answer is (b) It degenerates within 24 hours.

Chapter: Reproductive Physiology; Topic: Oogenesis; Subtopic: Meiotic Divisions in Female Gametogenesis

Keyword Definitions:
• Oogenesis: The process of formation and maturation of the female gamete (ovum) from oogonia.
• Polar body: Small cells produced during meiosis in oogenesis that usually degenerate and do not form gametes.
• Meiosis: A special type of cell division that halves the chromosome number, essential for gamete formation.
• Fertilization: The fusion of the male and female gametes to form a zygote.

Lead Question - 2014
First polar body is formed after?
a) Mitosis
b) First meiosis
c) Second meiosis
d) Fertilization

Explanation: During oogenesis, the primary oocyte undergoes the first meiotic division just before ovulation, producing a secondary oocyte and the first polar body. This polar body receives minimal cytoplasm and eventually degenerates. Hence, the correct answer is (b) First meiosis. The second polar body forms only after fertilization, marking meiosis II completion.

1. Second polar body is formed after?
a) Meiosis I
b) Meiosis II
c) Ovulation
d) Fertilization
Explanation: The secondary oocyte completes its second meiotic division only after fertilization, producing the second polar body and the mature ovum nucleus. This ensures a haploid zygote after sperm fusion. Therefore, the correct answer is (b) Meiosis II.

2. In which stage of meiosis is the primary oocyte arrested until puberty?
a) Prophase I
b) Metaphase I
c) Anaphase II
d) Telophase II
Explanation: The primary oocyte remains arrested in the diplotene stage of prophase I until puberty. Hormonal surges during the menstrual cycle resume meiosis, leading to ovulation. Thus, the correct answer is (a) Prophase I.

3. Clinical: A 25-year-old woman’s oocyte shows arrest in metaphase II. When does it complete meiosis?
a) During ovulation
b) After fertilization
c) Before fertilization
d) During implantation
Explanation: The secondary oocyte remains arrested in metaphase II until a sperm penetrates the zona pellucida. Only after fertilization does it complete meiosis II, forming the ovum and second polar body. Hence, the correct answer is (b) After fertilization.

4. Total number of polar bodies formed from one oogonium is?
a) One
b) Two
c) Three
d) Four
Explanation: One oogonium yields one mature ovum and two or sometimes three polar bodies. These polar bodies are by-products of meiosis I and II and usually degenerate. Thus, the correct answer is (b) Two.

5. Which hormone triggers the completion of meiosis I in the oocyte?
a) FSH
b) LH
c) Progesterone
d) Estrogen
Explanation: The LH surge during the mid-cycle triggers the completion of meiosis I in the primary oocyte, forming the secondary oocyte and the first polar body. This process prepares the oocyte for ovulation. Therefore, the correct answer is (b) LH.

6. Clinical: A woman with anovulation is treated with clomiphene citrate. What process does it enhance?
a) Mitosis of oogonia
b) Completion of meiosis I
c) Formation of zygote
d) Follicle degeneration
Explanation: Clomiphene citrate enhances LH and FSH release by blocking estrogen receptors, leading to follicular maturation and completion of meiosis I. It induces ovulation in anovulatory cycles. Hence, the correct answer is (b) Completion of meiosis I.

7. The process of extrusion of the first polar body occurs during?
a) Follicular phase
b) Ovulatory phase
c) Luteal phase
d) Menstrual phase
Explanation: The extrusion of the first polar body occurs just before ovulation during the ovulatory phase, after meiosis I completion. This is driven by the LH surge. The correct answer is (b) Ovulatory phase.

8. Clinical: A secondary oocyte has 23 chromosomes. How many chromatids does it have?
a) 23
b) 46
c) 92
d) 69
Explanation: The secondary oocyte contains 23 chromosomes, each with two chromatids (duplicated DNA). Hence, the total chromatid count is 46. Upon completion of meiosis II after fertilization, chromatids separate to restore the haploid condition. Thus, the correct answer is (b) 46.

9. Which structure degenerates to form the corpus albicans if fertilization does not occur?
a) Primary oocyte
b) Secondary oocyte
c) Corpus luteum
d) Graafian follicle
Explanation: After ovulation, the ruptured Graafian follicle becomes the corpus luteum. If fertilization fails, the corpus luteum degenerates to form a fibrous tissue called corpus albicans. The correct answer is (c) Corpus luteum.

10. Clinical: A woman’s oocyte fails to extrude the first polar body. Which phase of meiosis is affected?
a) Prophase I
b) Metaphase I
c) Anaphase I
d) Telophase I
Explanation: The extrusion of the first polar body occurs at the end of telophase I. A defect here prevents normal segregation of chromosomes, leading to aneuploidy or infertility. Hence, the correct answer is (d) Telophase I.

Chapter: Reproductive Physiology; Topic: Female Reproductive Hormones; Subtopic: Corpus Luteum and Its Regression

Keyword Definitions:
• Corpus luteum: A temporary endocrine gland formed after ovulation from the ruptured follicle that secretes progesterone.
• Ovulation: The release of a mature ovum from the ovary into the fallopian tube.
• Progesterone: A hormone responsible for maintaining endometrial receptivity for implantation.
• Regression: The process of degeneration or atrophy of the corpus luteum in the absence of pregnancy.

Lead Question - 2014
Corpus luteum starts regressing after how many days of ovulation?
a) 5 days
b) 10 days
c) 24 days
d) None

Explanation: The corpus luteum functions for approximately 14 days after ovulation, secreting progesterone to maintain the endometrium. In the absence of fertilization, it begins to regress around the 10th day post-ovulation, leading to menstruation. If pregnancy occurs, hCG maintains it. Thus, the correct answer is (b) 10 days.

1. Corpus luteum is mainly formed from which ovarian structure?
a) Graafian follicle
b) Primordial follicle
c) Theca externa
d) Zona pellucida
Explanation: After ovulation, the ruptured Graafian follicle transforms into the corpus luteum. The granulosa cells and theca interna cells undergo luteinization, producing progesterone. This hormone supports the endometrial lining for possible implantation. Therefore, the correct answer is (a) Graafian follicle.

2. Which hormone maintains the corpus luteum during early pregnancy?
a) LH
b) FSH
c) hCG
d) Estrogen
Explanation: During early pregnancy, human chorionic gonadotropin (hCG) secreted by trophoblast cells prevents luteal regression and maintains progesterone secretion. LH maintains the luteal phase in a normal cycle but not during pregnancy. Hence, the correct answer is (c) hCG.

3. Which of the following hormones decreases when the corpus luteum regresses?
a) FSH
b) Progesterone
c) Estrogen
d) GnRH
Explanation: When the corpus luteum regresses, progesterone and estrogen levels fall sharply. This hormonal drop triggers menstruation and FSH rise for the next cycle. Therefore, the correct answer is (b) Progesterone.

4. In a 28-day cycle, corpus luteum regresses around which day?
a) 7th day
b) 10th day
c) 24th day
d) 28th day
Explanation: In a typical 28-day cycle, ovulation occurs around day 14, and the corpus luteum regresses near day 24 if fertilization does not occur. Its regression leads to hormonal decline and onset of menstruation. Hence, the correct answer is (c) 24th day.