Human Reproduction

Topic: Fertilization and Twins; Subtopic: Types of Twins

Keyword Definitions:

• Monozygotic Twins: Twins formed from a single fertilized egg that splits into two embryos, genetically identical and always same-sex.

• Dizygotic (Fraternal) Twins: Twins formed from two separate eggs fertilized by two different sperms; genetically distinct and may be same or different sexes.

• In Vitro Fertilization (IVF): A process where an egg and sperm are combined outside the body to achieve fertilization.

• Genetic Similarity: Monozygotic twins share 100% of genes, while dizygotic twins share about 50% of genetic material.

Lead Question - 2025
Twins are born to a family that lives next door to you. The twins are a boy and a girl. Which of the following must be true?
(1) They are monozygotic twins
(2) They are fraternal twins
(3) They were conceived through in vitro fertilization
(4) They have 75% identical genetic content

Explanation: The correct answer is (2) They are fraternal twins. Monozygotic twins always have the same genetic composition and are of the same sex. Since the twins here are a boy and a girl, they must have originated from two different eggs fertilized by two different sperms. Therefore, they are dizygotic or fraternal twins, sharing roughly 50% of their genes.

1. Which hormone is responsible for the process of ovulation?
(1) FSH
(2) LH
(3) Progesterone
(4) Estrogen
Explanation: The correct answer is (2) LH. The luteinizing hormone surge triggers the rupture of the mature Graafian follicle, leading to ovulation and release of the secondary oocyte into the fallopian tube for potential fertilization.

2. Which of the following structures is formed immediately after fertilization?
(1) Zygote
(2) Morula
(3) Blastocyst
(4) Embryo
Explanation: The correct answer is (1) Zygote. Fertilization results in the fusion of male and female gametes to form a single diploid cell called the zygote, marking the beginning of embryonic development.

3. Which membrane forms the placenta during pregnancy?
(1) Chorion
(2) Amnion
(3) Yolk sac
(4) Allantois
Explanation: The correct answer is (1) Chorion. The chorion develops chorionic villi that invade the uterine tissue and help form the placenta, which facilitates nutrient, gas, and waste exchange between mother and fetus.

4. In which part of the female reproductive system does fertilization usually occur?
(1) Ovary
(2) Uterus
(3) Ampulla of fallopian tube
(4) Cervix
Explanation: The correct answer is (3) Ampulla of fallopian tube. Fertilization normally takes place in the ampullary region of the oviduct, where the sperm meets the ovum for fusion and zygote formation.

5. Which of the following prevents polyspermy during fertilization?
(1) Cortical reaction
(2) Acrosomal reaction
(3) Meiotic division
(4) Hormonal change
Explanation: The correct answer is (1) Cortical reaction. After the sperm fuses with the ovum, cortical granules release enzymes that harden the zona pellucida, preventing entry of additional sperms and ensuring monospermy.

6. Which statement correctly defines implantation?
(1) Attachment of blastocyst to the uterine wall
(2) Formation of zygote
(3) Division of morula
(4) Growth of embryo in oviduct
Explanation: The correct answer is (1) Attachment of blastocyst to the uterine wall. Implantation occurs about 6–7 days after fertilization when the blastocyst embeds into the endometrium for further development.

7. Assertion–Reason Type:
Assertion (A): Monozygotic twins share identical DNA.
Reason (R): They originate from two different eggs fertilized by two different sperms.
(1) A and R are true, R is the correct explanation of A
(2) A and R are true, but R is not the correct explanation
(3) A is true, R is false
(4) A is false, R is true
Explanation: The correct answer is (3). Monozygotic twins arise from a single fertilized egg that splits, hence have identical DNA. The reason given is incorrect because it describes dizygotic twins, not monozygotic ones.

8. Matching Type:
Match the following:
A. LH → i. Ovulation
B. FSH → ii. Follicle growth
C. Progesterone → iii. Maintenance of endometrium
D. HCG → iv. Supports corpus luteum
(1) A-i, B-ii, C-iii, D-iv
(2) A-ii, B-i, C-iv, D-iii
(3) A-i, B-iii, C-iv, D-ii
(4) A-iv, B-i, C-ii, D-iii
Explanation: The correct answer is (1). LH induces ovulation, FSH promotes follicular growth, progesterone maintains endometrium for implantation, and hCG preserves corpus luteum during early pregnancy to continue progesterone secretion.

9. Fill in the Blanks:
The hormone responsible for maintaining pregnancy is ______.
(1) LH
(2) Estrogen
(3) Progesterone
(4) Oxytocin
Explanation: The correct answer is (3) Progesterone. It prepares and maintains the uterine lining for implantation, suppresses uterine contractions, and supports the developing embryo throughout pregnancy.

10. Choose the Correct Statements:
Statement I: Identical twins always have the same blood group.
Statement II: Fraternal twins may have different blood groups.
(1) Both statements are true
(2) Both statements are false
(3) Statement I is true, II is false
(4) Statement I is false, II is true
Explanation: The correct answer is (1) Both statements are true. Since identical twins share identical genes, they have the same blood group. Fraternal twins have separate genetic combinations, so their blood groups may differ based on parental gene inheritance.

Topic: Menstrual Cycle; Subtopic: Menarche and Menopause

Keyword Definitions:

• Menarche: The onset of the first menstrual cycle in females, marking the beginning of reproductive life.

• Menopause: The permanent cessation of menstruation in females, indicating the end of reproductive years.

• Ovulation: The release of a mature ovum from the ovary into the fallopian tube for fertilization.

• Menstrual Cycle: A series of cyclic events in females involving the preparation of the uterus and ovary for fertilization.

• Hormones Involved: FSH, LH, estrogen, and progesterone regulate the menstrual cycle and ovulation.

Lead Question – 2025

The first menstruation is called:

(1) Menopause
(2) Menarche
(3) Diapause
(4) Ovulation

Explanation:
The first menstrual bleeding at puberty is called menarche. It usually occurs between the ages of 10 and 14, signaling the onset of reproductive maturity in females. Menarche results from the cyclic changes in ovarian hormones that prepare the uterus for pregnancy. Hence, the correct answer is (2) Menarche.

Guessed Questions:

1. The last menstrual cycle in a woman’s life is called:
(1) Menarche
(2) Ovulation
(3) Menopause
(4) Fertilization
Explanation: The permanent stoppage of menstruation at the end of a woman’s reproductive life is called menopause. It usually occurs between 45–50 years and is caused by the decline in ovarian hormone production. Hence, the correct answer is (3) Menopause.

2. Which hormone stimulates ovulation in females?
(1) Estrogen
(2) Progesterone
(3) LH (Luteinizing Hormone)
(4) FSH (Follicle Stimulating Hormone)
Explanation: Luteinizing hormone (LH) secreted by the anterior pituitary gland triggers the rupture of the mature Graafian follicle, releasing the ovum during ovulation. It also helps in corpus luteum formation, which secretes progesterone. Hence, the correct answer is (3) LH.

3. During which phase of the menstrual cycle does ovulation occur?
(1) Follicular phase
(2) Luteal phase
(3) Menstrual phase
(4) Mid-cycle
Explanation: Ovulation occurs approximately on the 14th day of a 28-day menstrual cycle, marking the mid-cycle phase. It follows the follicular phase and precedes the luteal phase, releasing a mature ovum ready for fertilization. Hence, the correct answer is (4) Mid-cycle.

4. Which hormone is responsible for the repair and regeneration of the endometrium after menstruation?
(1) Progesterone
(2) Estrogen
(3) LH
(4) FSH
Explanation: Estrogen, secreted by developing ovarian follicles during the follicular phase, stimulates the proliferation of the endometrial lining after menstruation, preparing the uterus for possible implantation. Hence, the correct answer is (2) Estrogen.

5. What is the typical duration of the menstrual cycle in human females?
(1) 14 days
(2) 21 days
(3) 28 days
(4) 35 days
Explanation: The average menstrual cycle lasts for about 28 days, though it may vary between 21 and 35 days in healthy women. The cycle consists of menstrual, follicular, ovulatory, and luteal phases. Hence, the correct answer is (3) 28 days.

6. Which gland controls the menstrual cycle through its hormones?
(1) Thyroid gland
(2) Pituitary gland
(3) Adrenal gland
(4) Pineal gland
Explanation: The anterior pituitary gland regulates the menstrual cycle by secreting FSH and LH. These hormones control follicle maturation, ovulation, and corpus luteum function in coordination with ovarian hormones. Hence, the correct answer is (2) Pituitary gland.

7. Assertion–Reason Type:
Assertion (A): Menarche marks the onset of reproductive phase in females.
Reason (R): It occurs due to increased secretion of FSH and LH leading to ovarian follicle maturation.
(1) Both A and R are true, and R explains A
(2) Both A and R are true, but R does not explain A
(3) A is true, R is false
(4) A is false, R is true
Explanation: Menarche occurs when the hypothalamic-pituitary-ovarian axis matures, increasing FSH and LH secretion, which stimulate follicle development and menstruation onset. Hence, both A and R are true, and R correctly explains A. The correct answer is (1).

8. Matching Type:
Match List I with List II:
A. FSH – 1. Stimulates follicular growth
B. LH – 2. Induces ovulation
C. Estrogen – 3. Regenerates endometrium
D. Progesterone – 4. Maintains endometrium
(1) A–1, B–2, C–3, D–4
(2) A–2, B–1, C–4, D–3
(3) A–4, B–3, C–2, D–1
(4) A–3, B–4, C–1, D–2
Explanation: FSH promotes follicle development, LH induces ovulation, estrogen rebuilds the endometrium, and progesterone maintains it for implantation. Thus, the correct match is (1) A–1, B–2, C–3, D–4.

9. Fill in the Blanks:
The hormone responsible for maintaining the endometrium after ovulation is ________.
(1) Estrogen
(2) FSH
(3) LH
(4) Progesterone
Explanation: Progesterone secreted by the corpus luteum thickens and maintains the endometrial lining after ovulation, preparing it for implantation. Its withdrawal leads to menstruation if fertilization does not occur. Hence, the correct answer is (4) Progesterone.

10. Choose the Correct Statements:
Statement I: Menarche indicates the beginning of reproductive maturity in females.
Statement II: Menopause occurs at puberty.
(1) Both statements are correct
(2) Both statements are incorrect
(3) Statement I correct, Statement II incorrect
(4) Statement I incorrect, Statement II correct
Explanation: Menarche is the first menstrual cycle marking the start of fertility, while menopause occurs at the end of reproductive life. Hence, Statement I is correct, and Statement II is incorrect. The correct answer is (3).

Topic: Gametogenesis; Subtopic: Oogenesis and Spermatogenesis – Comparative Study

Keyword Definitions:
• Oogenesis: The process of formation of female gametes (ova) in the ovary through meiotic division.
• Spermatogenesis: The process of formation of male gametes (sperms) in the seminiferous tubules of testes.
• Luteinizing Hormone (LH): A pituitary hormone that triggers ovulation and corpus luteum formation in females.
• Polar body: Small haploid cell formed during oogenesis that usually does not develop into an ovum.
• Endometrium: The inner lining of the uterus that thickens during the menstrual cycle to support implantation.

Lead Question - 2025

Consider the following:
A. The reductive division for the human female gametogenesis starts earlier than that of the male gametogenesis.
B. The gap between the first meiotic division and the second meiotic division is much shorter for males compared to females.
C. The first polar body is associated with the formation of the primary oocyte.
D. Luteinizing Hormone (LH) surge leads to disintegration of the endometrium and onset of menstrual bleeding.
Choose the correct answer from the options given below:
(1) A and B are true
(2) A and C are true
(3) B and D are true
(4) B and C are true

Explanation: Oogenesis begins before birth, whereas spermatogenesis starts at puberty, making statement A true. The gap between meiosis I and II is shorter in males, as spermatocytes rapidly complete division, supporting statement B. Statement C is incorrect because the first polar body forms after the completion of meiosis I. Statement D is incorrect since the LH surge causes ovulation, not menstrual bleeding. Hence, the correct answer is (1). This timing difference in gametogenesis reflects reproductive adaptations between sexes.

1. During which stage of life does oogenesis begin in human females?
(1) At birth
(2) During puberty
(3) During fetal development
(4) At menopause
Explanation: Oogenesis starts during fetal development when oogonia undergo mitosis and enter meiosis I to form primary oocytes. These remain arrested in prophase I until puberty. Thus, oogenesis begins much earlier than spermatogenesis. The correct answer is (3). This early onset explains why female gamete formation is limited and age-dependent.

2. The first meiotic division in oogenesis results in the formation of
(1) Two secondary oocytes
(2) One ovum and one polar body
(3) One secondary oocyte and one polar body
(4) Two ova
Explanation: The primary oocyte completes meiosis I during ovulation to form one large secondary oocyte and one small polar body. Unequal cytokinesis ensures nutrient concentration in the oocyte. The correct answer is (3). This division maintains chromosome number while preparing the oocyte for fertilization.

3. In human males, spermatogenesis is regulated by
(1) LH and FSH
(2) Estrogen and Progesterone
(3) Oxytocin and Vasopressin
(4) Prolactin and Relaxin
Explanation: Spermatogenesis is controlled by Follicle Stimulating Hormone (FSH), which acts on Sertoli cells, and Luteinizing Hormone (LH), which stimulates Leydig cells to secrete testosterone. Together, they promote sperm production. The correct answer is (1). Balanced hormone levels ensure normal male fertility and spermatogenic activity.

4. The LH surge in females is responsible for
(1) Follicle maturation
(2) Ovulation
(3) Menstrual bleeding
(4) Corpus luteum degeneration
Explanation: The LH surge occurs around the 14th day of the menstrual cycle and triggers rupture of the Graafian follicle to release the ovum. It also induces the formation of the corpus luteum. Hence, the correct answer is (2). LH surge is the key event marking the transition from follicular to luteal phase.

5. The first polar body is formed during
(1) Mitotic division
(2) First meiotic division
(3) Second meiotic division
(4) Fertilization
Explanation: The first polar body forms when the primary oocyte completes meiosis I, resulting in one secondary oocyte and a small non-functional polar body. This process ensures halving of the chromosome number. The correct answer is (2). The polar body usually degenerates, serving no reproductive role.

6. Which of the following statements is true regarding spermatogenesis?
(1) Begins during embryonic life
(2) Starts at puberty and continues throughout life
(3) Ends at puberty
(4) Occurs only once in lifetime
Explanation: Spermatogenesis starts at puberty under the influence of gonadotropins and continues throughout a male’s life. Continuous stem cell division ensures a constant sperm supply. The correct answer is (2). This lifelong process contrasts with oogenesis, which is finite and age-limited.

7. Assertion-Reason Question:
Assertion (A): Spermatogenesis occurs in seminiferous tubules.
Reason (R): Sertoli cells provide nourishment and support to developing spermatogenic cells.
(1) Both A and R are true and R is the correct explanation of A
(2) Both A and R are true but R is not the correct explanation of A
(3) A is true but R is false
(4) A is false but R is true
Explanation: Spermatogenesis takes place in seminiferous tubules where Sertoli cells regulate germ cell development through hormonal and nutritional support. Hence, both statements are true, and R correctly explains A. The correct answer is (1). This interaction is essential for maturation and release of spermatozoa.

8. Matching Type Question:
Match List I with List II:
List I        List II
A. Oogonia        I. Form primary oocytes
B. Primary oocyte        II. Completes meiosis I
C. Secondary oocyte        III. Completes meiosis II after fertilization
D. Ovum        IV. Haploid egg cell
(1) A-I, B-II, C-III, D-IV
(2) A-II, B-I, C-III, D-IV
(3) A-I, B-II, C-IV, D-III
(4) A-I, B-III, C-II, D-IV
Explanation: Oogonia divide to form primary oocytes, which complete meiosis I to form secondary oocytes and first polar body. The secondary oocyte completes meiosis II only after fertilization to produce an ovum. Hence, the correct matches are A–I, B–II, C–III, D–IV. The correct answer is (1).

9. Fill in the Blanks Question:
The process of formation of sperm is called __________.
(1) Oogenesis
(2) Spermatogenesis
(3) Fertilization
(4) Ovulation
Explanation: The process of sperm formation in the testes is termed spermatogenesis. It involves mitotic, meiotic, and maturation stages under hormonal regulation. The correct answer is (2). It ensures the continuous production of male gametes capable of fertilizing an ovum to form a zygote.

10. Choose the Correct Statements Question:
Statement I: Oogenesis begins before birth in females.
Statement II: Spermatogenesis starts before birth in males.
(1) Both statements are correct
(2) Both statements are incorrect
(3) Statement I is correct and Statement II is incorrect
(4) Statement I is incorrect and Statement II is correct
Explanation: In females, oogenesis begins before birth, whereas in males, spermatogenesis starts only at puberty. Thus, statement I is correct, and statement II is incorrect. The correct answer is (3). This fundamental timing difference defines distinct reproductive strategies in humans.

Chapter: Human Reproduction Topic: Pregnancy and Embryonic Development Subtopic: Organogenesis and Foetal Growth

Keyword Definitions:

• Gestation: Period from fertilization to birth, about 280 days in humans.

• Organogenesis: Formation of organs during embryonic development.

• Embryo: Developing organism up to 8 weeks after fertilization.

• Foetus: The stage after 8 weeks until birth when organs mature.

• Placenta: A temporary organ that connects the foetus to the uterus for exchange of gases and nutrients.

Lead Question (2025)

Find the correct statements:

A. In human pregnancy, the major organ systems are formed at the end of 12 weeks.

B. In human pregnancy, the major organ systems are formed at the end of 8 weeks.

C. In human pregnancy, the heart is formed after one month of gestation.

D. In human pregnancy, limbs and digits develop by the end of the second month.

E. In human pregnancy, appearance of hair is usually observed in the fifth month.

Choose the correct answer from the options given below:

(1) A and E only

(2) B and C only

(3) B, C, D and E only

(4) A, C, D and E only

Explanation:

The embryonic period lasts up to 8 weeks during which organogenesis occurs. The heart forms and starts beating around the 4th week. Limbs and digits develop by the 8th week, while hair appears during the 5th month of gestation. Thus, statements B, C, D and E are correct.

Answer: (3) B, C, D and E only.

1. During which week does the human embryo’s heart begin to beat?

(1) 2nd week

(2) 4th week

(3) 8th week

(4) 12th week

Explanation:

The human heart starts beating by the end of the 3rd week and becomes functional by the 4th week of gestation. Early circulation is crucial for delivering nutrients and oxygen to developing organs through the embryo’s vascular system.

Answer: (2) 4th week.

2. The placenta performs all of the following functions except—

(1) Nutrition

(2) Excretion

(3) Hormone secretion

(4) Oxygen utilization by the foetus

Explanation:

The placenta facilitates gas exchange, nutrient transfer, and waste removal between the mother and foetus. It also secretes hormones such as hCG, progesterone, and oestrogen. Oxygen utilization occurs in foetal tissues, not in the placenta itself.

Answer: (4) Oxygen utilization by the foetus.

3. Which of the following structures is derived from the ectoderm?

(1) Liver

(2) Brain

(3) Heart

(4) Gonads

Explanation:

The ectoderm gives rise to the nervous system, epidermis, and sensory organs. The brain and spinal cord develop from the ectoderm, while the liver arises from the endoderm and the heart from the mesoderm.

Answer: (2) Brain.

4. Assertion (A): Placenta acts as an endocrine tissue.

Reason (R): It secretes hormones like hCG, estrogen, and progesterone.

(1) Both A and R are true and R is the correct explanation of A

(2) Both A and R are true but R is not the correct explanation of A

(3) A is true but R is false

(4) A is false but R is true

Explanation:

The placenta functions as an endocrine organ producing hCG, progesterone, and estrogen, essential for maintaining pregnancy. Thus, both Assertion and Reason are true, and R correctly explains A.

Answer: (1) Both A and R are true and R is the correct explanation of A.

5. Match the following:

List I (Structure) – List II (Function)

A. Amnion – (i) Nutrient supply

B. Chorion – (ii) Protection of embryo

C. Yolk sac – (iii) Forms placenta

D. Placenta – (iv) Exchange of gases

(1) A–ii, B–iii, C–i, D–iv

(2) A–iii, B–ii, C–iv, D–i

(3) A–iv, B–ii, C–iii, D–i

(4) A–i, B–iii, C–ii, D–iv

Explanation:

Amnion protects the embryo with amniotic fluid. Chorion contributes to placenta formation. Yolk sac provides early nutrients. Placenta facilitates exchange of gases and waste between mother and foetus.

Answer: (1) A–ii, B–iii, C–i, D–iv.

6. During which month does ossification of foetal bones begin?

(1) 1st month

(2) 2nd month

(3) 3rd month

(4) 5th month

Explanation:

Ossification begins around the third month of gestation when cartilage is replaced by bone tissue. It indicates transition from embryonic to foetal stage and is vital for skeletal formation and body structure support.

Answer: (3) 3rd month.

7. Which hormone maintains the corpus luteum during early pregnancy?

(1) Progesterone

(2) Estrogen

(3) Human Chorionic Gonadotropin (hCG)

(4) Relaxin

Explanation:

hCG, secreted by trophoblast cells, maintains the corpus luteum during early pregnancy. It ensures continuous progesterone secretion, essential for maintaining the endometrium and supporting implantation and early embryonic growth.

Answer: (3) Human Chorionic Gonadotropin (hCG).

8. Fill in the Blank:

The fluid that surrounds and protects the developing embryo in the uterus is called __________.

(1) Chorionic fluid

(2) Peritoneal fluid

(3) Amniotic fluid

(4) Synovial fluid

Explanation:

The developing embryo is enclosed in the amniotic sac filled with amniotic fluid. This fluid cushions the embryo, maintains temperature, and prevents dehydration and injury during development.

Answer: (3) Amniotic fluid.

9. Choose the correct statements (Statement I & Statement II):

Statement I: The placenta allows diffusion of nutrients and gases between maternal and foetal blood.

Statement II: Maternal and foetal blood directly mix within placental villi.

(1) Both statements are correct

(2) Both statements are incorrect

(3) Statement I is correct, Statement II is incorrect

(4) Statement I is incorrect, Statement II is correct

Explanation:

In the placenta, maternal and foetal blood remain separated by thin membranes. Nutrients, gases, and wastes exchange through diffusion without direct blood mixing. Hence only Statement I is correct.

Answer: (3) Statement I is correct, Statement II is incorrect.

10. Which of the following marks the beginning of the foetal period?

(1) Fertilization

(2) Completion of organogenesis

(3) Implantation

(4) Birth

Explanation:

The foetal period begins after organogenesis is completed, i.e., by the end of the 8th week. During this stage, the organs grow and mature until birth, marking rapid structural and functional development.

Answer: (2) Completion of organogenesis.

Topic: Structure of Sperm; Subtopic: Functional parts and their roles

Keyword Definitions:
• Acrosome: A cap-like structure containing enzymes for egg penetration.
• Middle Piece: The portion of the sperm rich in mitochondria that provides energy.
• Tail: Responsible for sperm motility through flagellar movement.
• Head: Contains nucleus carrying genetic material.

Lead Question – 2025
Match List - I with List - II
List - I      List - II
A. Head             I. Enzymes
B. Middle piece   II. Sperm motility
C. Acrosome       III. Energy
D. Tail               IV. Genetic material

(1) A-IV, B-III, C-I, D-II
(2) A-IV, B-III, C-II, D-I
(3) A-III, B-IV, C-II, D-I
(4) A-III, B-II, C-I, D-IV

Explanation:
The sperm consists of four key parts: the head containing the nucleus (genetic material), the acrosome filled with hydrolytic enzymes aiding fertilization, the middle piece packed with mitochondria supplying ATP for motility, and the tail propelling movement. Thus, the correct matching is A-IV, B-III, C-I, D-II. The sperm’s structure ensures efficient transport and successful fertilization of the ovum.

1. Which part of the sperm contains hydrolytic enzymes aiding in penetration of the egg?
(1) Head
(2) Middle piece
(3) Acrosome
(4) Tail

Explanation:
The acrosome is a cap-like structure located at the tip of the sperm head. It contains hydrolytic enzymes such as hyaluronidase and acrosin that help the sperm penetrate the zona pellucida of the ovum, allowing fertilization. Therefore, the correct answer is (3) Acrosome.

2. Which organelle is abundant in the middle piece of sperm?
(1) Golgi apparatus
(2) Ribosomes
(3) Mitochondria
(4) Lysosomes

Explanation:
The middle piece of sperm is densely packed with mitochondria, which generate ATP to power the movement of the tail (flagellum). This energy is essential for the sperm’s motility through the female reproductive tract toward the egg. Therefore, the correct answer is (3) Mitochondria.

3. The nucleus of the sperm is located in which region?
(1) Acrosome
(2) Head
(3) Middle piece
(4) Tail

Explanation:
The head of the sperm houses the nucleus, which contains densely packed chromatin (haploid set of chromosomes). This genetic material is delivered into the ovum during fertilization. Hence, the correct answer is (2) Head, as it is the part responsible for carrying paternal DNA to the egg.

4. The function of the sperm tail is to
(1) Provide energy
(2) Store enzymes
(3) Help in motility
(4) Carry nucleus

Explanation:
The tail of the sperm functions as a propelling organ, enabling movement through whip-like flagellar action. Powered by ATP from the mitochondria in the middle piece, this movement is essential for the sperm to reach and fertilize the ovum. Thus, the correct answer is (3) Help in motility.

5. Assertion (A): The middle piece of the sperm provides energy for motility.
Reason (R): The middle piece contains mitochondria that release ATP.
(1) Both A and R are true, and R is the correct explanation of A.
(2) Both A and R are true, but R is not the correct explanation of A.
(3) A is true, R is false.
(4) A is false, R is true.

Explanation:
Both assertion and reason are true and interrelated. The mitochondria in the middle piece supply ATP required for flagellar beating and sperm movement. Thus, R correctly explains A. The correct answer is (1) Both A and R are true, and R is the correct explanation of A.

6. Which of the following correctly represents the energy source for sperm motility?
(1) Glycogen
(2) ATP from mitochondria
(3) Fatty acids
(4) Lactic acid

Explanation:
The mitochondria located in the middle piece of the sperm synthesize ATP through oxidative phosphorylation, serving as the primary energy source for flagellar movement. This continuous ATP supply ensures efficient motility of the sperm toward the ovum. Hence, the correct answer is (2) ATP from mitochondria.

7. (Matching Type)
Match the following:
A. Head – 1. Motility
B. Acrosome – 2. Enzymes
C. Middle piece – 3. Energy
D. Tail – 4. Genetic material

(1) A-4, B-2, C-3, D-1
(2) A-2, B-1, C-3, D-4
(3) A-3, B-4, C-1, D-2
(4) A-4, B-3, C-2, D-1

Explanation:
The head contains genetic material, the acrosome carries enzymes, the middle piece generates energy, and the tail aids motility. Hence, the correct matching is (1) A-4, B-2, C-3, D-1. Each part plays a vital role in the sperm’s overall structure and fertilizing ability.

8. (Fill in the Blanks)
The ______ of the sperm provides enzymes for ovum penetration.
(1) Acrosome
(2) Nucleus
(3) Middle piece
(4) Tail

Explanation:
The acrosome releases hydrolytic enzymes such as acrosin and hyaluronidase during fertilization. These enzymes help the sperm digest the outer layers of the ovum, facilitating the fusion of gametes. Therefore, the correct answer is (1) Acrosome.

9. (Choose the Correct Statements)
Statement I: The tail of the sperm contains mitochondria.
Statement II: The middle piece provides energy for motility.
(1) Both statements are true.
(2) Only Statement I is true.
(3) Only Statement II is true.
(4) Both statements are false.

Explanation:
The tail does not contain mitochondria; they are present in the middle piece. These mitochondria provide energy for flagellar movement. Thus, only Statement II is true. The correct answer is (3) Only Statement II is true.

10. Which structure of sperm is responsible for egg penetration during fertilization?
(1) Middle piece
(2) Acrosome
(3) Head
(4) Tail

Explanation:
The acrosome of sperm plays a critical role in fertilization. It contains enzymes that digest the zona pellucida, allowing the sperm nucleus to fuse with the egg. Hence, the correct answer is (2) Acrosome.

Topic: Menstrual Cycle; Subtopic: Role of Hormones in Menstrual Regulation

Keyword Definitions:
• Corpus Luteum: A temporary endocrine gland formed from the ruptured Graafian follicle after ovulation, secreting progesterone.
• Endometrium: The innermost lining of the uterus that thickens to support implantation and sheds during menstruation.
• Menarche: The first menstrual cycle in a female, marking the onset of reproductive maturity.
• Menopause: The natural cessation of menstruation, indicating the end of reproductive capability.
• Progesterone: A hormone that maintains the endometrial lining and inhibits uterine contractions during pregnancy.
• Fertilization: The fusion of sperm and ovum forming a zygote.
• Menstrual Cycle: A monthly cycle involving changes in the uterus and ovaries, typically lasting about 28 days.

Lead Question - 2024 (Jhajjhar)
Given below are two statements:

Statement I: Degeneration of corpus luteum in the absence of fertilization is the cause for disintegration of endometrium.
Statement II: Cyclic menstruation indicates normal reproductive phase in human females and extends between menarche and menopause.

Choose the correct answer from the options given below:
1. Both Statement I and Statement II are True.
2. Both Statement I and Statement II are False.
3. Statement I is True but Statement II is False.
4. Statement I is False but Statement II is True.

Explanation:
The correct answer is 1. Both Statement I and Statement II are True. When fertilization does not occur, the corpus luteum degenerates, reducing progesterone levels and leading to shedding of the endometrium. This results in menstruation. Regular menstruation between menarche and menopause reflects a normal, healthy reproductive phase in human females controlled by hormonal cycles.

1. Which hormone is primarily responsible for maintaining the endometrial lining during the luteal phase?
1. Estrogen
2. Progesterone
3. LH
4. FSH

Explanation:
The correct answer is 2. Progesterone. Secreted by the corpus luteum, progesterone maintains the endometrium, preparing it for implantation of the fertilized ovum. If fertilization does not occur, progesterone levels fall, leading to endometrial degeneration and the onset of menstruation, marking the end of one reproductive cycle.

2. Which of the following marks the end of the reproductive phase in females?
1. Menstruation
2. Menarche
3. Menopause
4. Ovulation

Explanation:
The correct answer is 3. Menopause. Menopause is the permanent cessation of menstruation, indicating the end of a woman’s reproductive period. It usually occurs between 45–55 years of age. During this phase, ovarian follicles decline, leading to decreased estrogen and progesterone secretion, and ending ovulatory cycles.

3. Which phase of the menstrual cycle involves rebuilding of the endometrium under estrogen influence?
1. Menstrual phase
2. Follicular phase
3. Ovulatory phase
4. Luteal phase

Explanation:
The correct answer is 2. Follicular phase. The follicular phase follows menstruation and is characterized by estrogen-driven proliferation of the endometrial lining. Follicles mature under FSH influence, and one becomes dominant. Rising estrogen levels prepare the uterus for potential implantation, leading up to ovulation around the 14th day of the cycle.

4. What triggers ovulation in the menstrual cycle?
1. A sudden surge in LH
2. A decline in FSH
3. Increased progesterone secretion
4. Endometrial shedding

Explanation:
The correct answer is 1. A sudden surge in LH. The mid-cycle luteinizing hormone (LH) surge induces the rupture of the mature Graafian follicle, releasing the secondary oocyte. This marks ovulation, usually occurring on the 14th day of a 28-day cycle. The remaining follicular cells form the corpus luteum, which secretes progesterone post-ovulation.

5. If fertilization occurs, what prevents degeneration of the corpus luteum?
1. High estrogen
2. Follicle Stimulating Hormone
3. Human Chorionic Gonadotropin (hCG)
4. Progesterone

Explanation:
The correct answer is 3. Human Chorionic Gonadotropin (hCG). hCG secreted by the developing embryo maintains the corpus luteum during early pregnancy. This ensures continued progesterone production to sustain the endometrial lining, preventing menstruation and supporting implantation and early embryonic development until the placenta forms its hormonal role.

6. What is the duration of the average menstrual cycle in humans?
1. 15 days
2. 21 days
3. 28 days
4. 35 days

Explanation:
The correct answer is 3. 28 days. The menstrual cycle typically lasts about 28 days, though variations from 26 to 32 days are common. It includes four phases—menstrual, follicular, ovulatory, and luteal—regulated by hormonal interplay among the hypothalamus, pituitary gland, and ovaries, ensuring coordinated reproductive readiness.

7. Assertion-Reason Question:
Assertion (A): Progesterone prevents uterine contractions during pregnancy.
Reason (R): Low progesterone levels trigger menstrual bleeding.

1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. (A) is False but (R) is True.

Explanation:
The correct answer is 2. Both (A) and (R) are True but (R) is not the correct explanation of (A). Progesterone inhibits uterine contractions to maintain pregnancy. However, its decline causes endometrial breakdown and menstruation, not directly linked to contraction inhibition but essential for cycle regulation.

8. Matching Type Question:
Match List-I with List-II:
List-I (Hormone) — List-II (Function)
A. FSH — I. Stimulates follicular growth
B. LH — II. Triggers ovulation
C. Progesterone — III. Maintains endometrium
D. Estrogen — IV. Promotes endometrial proliferation

1. A-I, B-II, C-III, D-IV
2. A-II, B-I, C-IV, D-III
3. A-IV, B-II, C-I, D-III
4. A-I, B-III, C-IV, D-II

Explanation:
The correct answer is 1. A-I, B-II, C-III, D-IV. FSH stimulates follicle growth, LH induces ovulation, progesterone maintains the endometrium, and estrogen rebuilds it after menstruation. Together, these hormones coordinate ovarian and uterine functions, ensuring regular menstrual cycles and successful reproduction.

9. Fill in the Blanks Question:
The corpus luteum secretes __________, which helps maintain the endometrial lining.
1. FSH
2. LH
3. Progesterone
4. Estrogen

Explanation:
The correct answer is 3. Progesterone. The corpus luteum forms after ovulation and secretes progesterone, which stabilizes and maintains the endometrial lining. If pregnancy occurs, progesterone continues to be secreted under hCG influence; otherwise, its decline leads to menstruation, restarting the reproductive cycle.

10. Choose the Correct Statements:
Statement I: Menstrual flow results from the breakdown of the endometrial lining.
Statement II: Menstrual bleeding occurs due to a rise in progesterone level.

1. Both statements are correct.
2. Both statements are incorrect.
3. Only Statement I is correct.
4. Only Statement II is correct.

Explanation:
The correct answer is 3. Only Statement I is correct. Menstrual bleeding occurs due to the shedding of the endometrial lining following progesterone withdrawal, not its increase. The fall in progesterone and estrogen levels causes rupture of endometrial blood vessels, leading to menstrual flow and the beginning of a new cycle.

Topic: Pregnancy and Embryonic Development; Subtopic: Placental Hormones and Their Functions

Keyword Definitions:
• Placenta: Temporary endocrine organ connecting fetus and mother, responsible for nutrient and gas exchange.
• hCG (Human Chorionic Gonadotropin): Hormone maintaining corpus luteum during early pregnancy.
• hPL (Human Placental Lactogen): Hormone promoting fetal growth and maternal glucose metabolism.
• Relaxin: Hormone secreted by ovary during pregnancy to relax pelvic ligaments.
• Inhibin: Hormone suppressing FSH secretion, secreted by ovary.
• Estrogen: Promotes uterine growth and blood flow.
• Progesterone: Maintains endometrial lining and prevents uterine contractions.
• Corpus luteum: Gland in ovary secreting progesterone until placenta develops.
• Endocrine function of placenta: Secretion of multiple hormones regulating pregnancy and fetal development.
• Fetoplacental unit: Functional association between fetus and placenta for hormonal and metabolic coordination.

Lead Question – (September 2024, Jhajjar)

Name the hormone(s) not secreted by placenta.
A. Estrogens
B. Progestogens
C. Relaxin and Inhibin
D. hCG
E. hPL

1. D and E only
2. C only
3. B only
4. A and C only

Explanation (Answer: Option 2)
The placenta secretes hCG, hPL, estrogens, and progesterone, all vital for maintaining pregnancy. However, Relaxin and Inhibin are not secreted by the placenta; they are produced by the ovary. Relaxin relaxes pelvic ligaments during parturition, and Inhibin suppresses FSH secretion, preventing multiple follicle maturation during pregnancy.

1. Single Correct Answer Type:
Which hormone maintains the corpus luteum during early pregnancy?
1. Progesterone
2. hCG
3. Estrogen
4. Relaxin

Explanation (Answer: Option 2)
Human Chorionic Gonadotropin (hCG) is secreted by the placenta soon after implantation. It maintains the corpus luteum in the ovary, ensuring continued secretion of progesterone during early pregnancy. This sustains the uterine lining and prevents menstruation, essential for embryo implantation and development.

2. Single Correct Answer Type:
Which hormone prepares mammary glands for lactation during pregnancy?
1. Estrogen
2. hPL
3. Relaxin
4. FSH

Explanation (Answer: Option 2)
Human Placental Lactogen (hPL) stimulates mammary gland development for lactation and regulates maternal glucose metabolism to supply energy for the growing fetus. It ensures a balance between maternal energy needs and fetal nutrition, supporting both during mid to late stages of pregnancy.

3. Single Correct Answer Type:
Which hormone prevents uterine contractions during pregnancy?
1. Progesterone
2. Estrogen
3. Oxytocin
4. Relaxin

Explanation (Answer: Option 1)
Progesterone is the key hormone that maintains pregnancy by inhibiting uterine muscle contractions, ensuring the embryo remains implanted. It also supports endometrial gland secretion, providing nutrients to the developing embryo until the placenta fully forms and takes over hormonal functions.

4. Single Correct Answer Type:
Which of the following is secreted by the ovary and not by placenta?
1. Estrogen
2. hCG
3. Relaxin
4. hPL

Explanation (Answer: Option 3)
Relaxin is secreted by the corpus luteum of the ovary during pregnancy. It helps relax pelvic ligaments and the cervix during parturition, facilitating childbirth. It is not secreted by the placenta, differentiating it from placental hormones like hCG, hPL, and progesterone.

5. Single Correct Answer Type:
The placenta functions as an endocrine gland because it:
1. Secretes digestive enzymes
2. Produces essential hormones
3. Transports oxygen to fetus
4. Removes fetal waste

Explanation (Answer: Option 2)
The placenta functions as an endocrine gland because it secretes hormones such as hCG, hPL, estrogen, and progesterone, which are vital for maintaining pregnancy, regulating metabolism, and preparing the body for parturition and lactation. Hence, it serves multiple functions including hormonal regulation.

6. Single Correct Answer Type:
Which placental hormone is similar in function to growth hormone?
1. Progesterone
2. hCG
3. hPL
4. Estrogen

Explanation (Answer: Option 3)
Human Placental Lactogen (hPL) has growth hormone-like and prolactin-like effects. It promotes protein synthesis and modifies maternal metabolism to ensure glucose and amino acid availability for the fetus. It also prepares mammary glands for lactation, making it a multifunctional hormone during pregnancy.

7. Fill in the Blanks Type:
During early pregnancy, the corpus luteum is maintained by ________.
1. Estrogen
2. Progesterone
3. hCG
4. Oxytocin

Explanation (Answer: Option 3)
The corpus luteum is maintained by Human Chorionic Gonadotropin (hCG) secreted by the developing placenta. This hormone ensures continued progesterone production by the corpus luteum, maintaining the uterine lining until the placenta fully takes over progesterone secretion later in pregnancy.

8. Matching Type:
Match the following hormones with their functions:
A. hCG — (i) Maintains corpus luteum
B. hPL — (ii) Prepares mammary glands for lactation
C. Relaxin — (iii) Relaxes pelvic ligaments
D. Progesterone — (iv) Prevents uterine contraction

1. A-(i), B-(ii), C-(iii), D-(iv)
2. A-(ii), B-(i), C-(iv), D-(iii)
3. A-(iii), B-(iv), C-(ii), D-(i)
4. A-(iv), B-(iii), C-(i), D-(ii)

Explanation (Answer: Option 1)
The correct match is A-(i), B-(ii), C-(iii), D-(iv). hCG maintains the corpus luteum, hPL prepares mammary glands, Relaxin relaxes pelvic ligaments, and Progesterone prevents uterine contractions, ensuring coordinated hormonal support during pregnancy and parturition.

9. Assertion-Reason Type:
Assertion (A): hCG helps maintain the corpus luteum during early pregnancy.
Reason (R): hCG is secreted by the pituitary gland of the mother.

1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.

Explanation (Answer: Option 3)
The assertion is true as hCG maintains the corpus luteum in early pregnancy. However, the reason is false because hCG is secreted by the placenta, not the pituitary gland. This hormone ensures progesterone production until the placenta takes over its secretion.

10. Choose the Correct Statements (Statement I & II):
Statement I: hCG is secreted by placenta to maintain corpus luteum.
Statement II: Relaxin is secreted by placenta to relax pelvic ligaments.

1. Both statements are true
2. Both statements are false
3. Statement I true, Statement II false
4. Statement I false, Statement II true

Explanation (Answer: Option 3)
Statement I is true as hCG is secreted by the placenta to maintain corpus luteum. Statement II is false because Relaxin is secreted by the ovary, not the placenta. Relaxin facilitates childbirth by softening pelvic ligaments, distinguishing it from placental hormones.

Topic: Embryonic Development; Subtopic: Stages of Embryonic Growth During Pregnancy

Keyword Definitions:

• Embryo: The early developmental stage of an organism following fertilization and before becoming a fetus.

• Fetus: The developing human from the ninth week of pregnancy until birth.

• Gestation: The period of development inside the uterus from conception to birth.

• Organogenesis: The stage during which organs begin to form in the embryo.

• Placenta: A temporary organ that facilitates exchange of nutrients, gases, and wastes between mother and fetus.

Lead Question - 2024 (Jhajjhar)

Match List I with List II relating to major features of embryonic development at different timings of pregnancy:
List I (No. of weeks)
A. After 4 weeks of pregnancy
B. After 12 weeks of pregnancy
C. After 24 weeks of pregnancy
D. After 8 weeks of pregnancy

List II (Major features)
I. Eye-lids separate and eyelashes are formed
II. Heart is formed
III. Limbs and digits are developed
IV. External genital organs are well developed

Choose the correct answer from the options given below:
1. A-III, B-IV, C-I, D-II
2. A-II, B-I, C-III, D-IV
3. A-II, B-IV, C-I, D-III
4. A-III, B-IV, C-II, D-I

Explanation: The correct answer is option 3 (A-II, B-IV, C-I, D-III). The human embryonic development progresses in defined stages. After 4 weeks, the heart forms and begins to beat. By 8 weeks, limbs and digits develop. After 12 weeks, external genital organs are well developed, and after 24 weeks, eyelids and eyelashes appear, marking advanced fetal differentiation and maturation.

Guessed Questions:

1. At which week of pregnancy does the human embryo’s heart begin to beat?
1. 2nd week
2. 4th week
3. 8th week
4. 10th week
Explanation: The correct answer is 2. The heart forms and starts beating by the 4th week of pregnancy. This marks the beginning of cardiovascular activity and is a crucial sign of embryonic life. Early detection via ultrasound confirms normal progression of embryonic development and cardiac function.

2. By the end of the 8th week, which major developmental change occurs in the embryo?
1. Formation of eyelids
2. Development of limbs and digits
3. Formation of placenta
4. Appearance of external genitalia
Explanation: The correct answer is 2. During the 8th week, limb buds elongate, and digits separate to form fingers and toes. This period marks the completion of organogenesis, where basic body plans are established before the fetal stage begins.

3. After how many weeks of pregnancy do the external genital organs become distinctly visible?
1. 4 weeks
2. 8 weeks
3. 12 weeks
4. 20 weeks
Explanation: The correct answer is 3. By the 12th week of gestation, external genitalia become well developed and distinguishable, allowing determination of fetal sex through imaging. This marks the early fetal phase with established organ systems and rapid growth.

4. At what stage do eyelids and eyelashes form during fetal development?
1. 8 weeks
2. 12 weeks
3. 16 weeks
4. 24 weeks
Explanation: The correct answer is 4. Around 24 weeks, the fetus develops eyelids that separate and eyelashes that begin to form. These developments signify the maturation of sensory organs as the fetus approaches viability in the later trimesters.

5. What is the primary function of the placenta during pregnancy?
1. Provides mechanical protection
2. Facilitates nutrient and gas exchange
3. Stores hormones
4. Produces digestive enzymes
Explanation: The correct answer is 2. The placenta acts as an interface between maternal and fetal blood, allowing transfer of oxygen, nutrients, and removal of waste products. It also secretes hormones like hCG and progesterone essential for maintaining pregnancy and fetal development.

6. Which hormone maintains the endometrium during pregnancy?
1. LH
2. Estrogen
3. Progesterone
4. FSH
Explanation: The correct answer is 3. Progesterone secreted initially by the corpus luteum and later by the placenta maintains the endometrial lining. It ensures a supportive uterine environment essential for implantation, nourishment, and sustained fetal development throughout gestation.

7. Assertion-Reason Type:
Assertion (A): Placenta acts as an endocrine gland during pregnancy.
Reason (R): It secretes hormones like hCG, estrogen, and progesterone.
1. Both A and R are true, and R is the correct explanation of A.
2. Both A and R are true, but R is not the correct explanation.
3. A is true, but R is false.
4. A is false, but R is true.
Explanation: The correct answer is 1. The placenta functions as an endocrine organ by releasing hormones such as hCG, estrogen, and progesterone, which regulate pregnancy maintenance and fetal growth, demonstrating its dual role as both nutritive and hormonal support system.

8. Matching Type:
Match the hormones with their respective functions:
A. hCG    I. Maintains corpus luteum
B. Relaxin    II. Softens pelvic ligaments
C. Oxytocin    III. Initiates uterine contractions
D. Prolactin    IV. Stimulates milk production

1. A-I, B-II, C-III, D-IV
2. A-II, B-I, C-IV, D-III
3. A-III, B-IV, C-I, D-II
4. A-IV, B-I, C-III, D-II
Explanation: The correct answer is 1. hCG maintains corpus luteum, Relaxin softens pelvic ligaments, Oxytocin triggers uterine contractions, and Prolactin promotes milk synthesis. These hormonal actions coordinate to ensure a successful pregnancy, childbirth, and lactation process.

9. Fill in the Blanks:
During pregnancy, the exchange of oxygen and nutrients between mother and fetus occurs through the __________.
1. Amnion
2. Placenta
3. Umbilical cord
4. Chorion
Explanation: The correct answer is 2. The placenta is a highly vascularized organ that facilitates diffusion of oxygen, nutrients, and waste products between maternal and fetal blood. It is attached to the uterine wall and connected to the fetus via the umbilical cord.

10. Choose the Correct Statements (Statement I & Statement II):
Statement I: Human gestation period lasts about 280 days.
Statement II: Parturition is initiated by maternal hormones only.
1. Both statements are correct.
2. Both statements are incorrect.
3. Statement I is correct but Statement II is incorrect.
4. Statement I is incorrect but Statement II is correct.
Explanation: The correct answer is 3. Human gestation averages 280 days (around 9 months). However, parturition is initiated by a combination of maternal and fetal hormones, mainly oxytocin and cortisol, that trigger uterine contractions and birth.

Topic: Male Reproductive System; Subtopic: Pathway of Sperm Transport and Accessory Ducts

Keyword Definitions:

• Spermatogenesis: Process of sperm formation occurring in seminiferous tubules of testes.

• Seminiferous Tubules: Coiled structures within the testis where sperm are produced.

• Rete Testis: Network of tubules that transport sperm from seminiferous tubules to vasa efferentia.

• Epididymis: Long coiled tube where sperm mature and gain motility.

• Vas Deferens: Muscular tube carrying mature sperm from epididymis to ejaculatory duct.

• Urethra: Common passage for urine and semen, opening at the tip of the penis.

Lead Question – (September 2024, Jhajjhar)

Arrange in a proper sequence the pathway of sperms from testis to outside in the human male reproductive system.

A. Vas deferens

B. Rete testis

C. Seminiferous tubules

D. Vasa efferentia

E. Urethra

F. Epididymis

Choose the correct answer from the options given below:

1. F → A → B → D → E → C

2. C → A → B → D → F → E

3. B → A → D → C → F → E

4. C → B → D → F → A → E

Explanation:

The correct sequence of sperm passage is C → B → D → F → A → E. Sperm are produced in seminiferous tubules, pass through rete testis, vasa efferentia, epididymis, vas deferens, and finally the urethra during ejaculation. Each part assists in maturation, transport, or storage of sperms. Answer: Option 4

1. Which of the following structures stores sperm temporarily and allows them to mature?

1. Seminiferous tubules

2. Rete testis

3. Epididymis

4. Vas deferens

Explanation:

The epididymis is a long, coiled structure on the posterior side of the testis. It stores sperms and allows them to mature and gain motility. It also absorbs excess fluid and secretes substances vital for sperm function. Answer: Option 3

2. Which part of the male reproductive system carries sperm from the epididymis to the ejaculatory duct?

1. Rete testis

2. Vasa efferentia

3. Vas deferens

4. Urethra

Explanation:

Vas deferens is a muscular tube that transports mature sperm from the epididymis to the ejaculatory duct during ejaculation. It also serves as a storage site for sperms until release. This duct joins the seminal vesicle to form the ejaculatory duct. Answer: Option 3

3. Assertion-Reason Type:

Assertion (A): Spermatozoa formed in seminiferous tubules are immotile when released.

Reason (R): They acquire motility in the epididymis where maturation occurs.

1. Both A and R are true, and R is the correct explanation.

2. Both A and R are true, but R is not the correct explanation.

3. A is true but R is false.

4. A is false but R is true.

Explanation:

Newly formed spermatozoa in seminiferous tubules are non-motile. They gain motility and fertilizing ability during storage in the epididymis due to secretions and environmental conditions. Hence, both statements are true, and R correctly explains A. Answer: Option 1

4. Fill in the Blanks:

The process of release of sperms from the seminiferous tubules into the lumen of the duct is called ________.

1. Ejaculation

2. Spermiation

3. Spermatogenesis

4. Capacitation

Explanation:

Spermiation is the process in which mature sperm are released from the Sertoli cells of the seminiferous tubules into the lumen. This marks the end of spermatogenesis, after which sperm move toward the epididymis for maturation. Answer: Option 2

5. Match the following:

List I        List II

A. Seminiferous tubules        I. Sperm maturation

B. Rete testis        II. Network of tubules within testis

C. Vas deferens        III. Sperm transport to urethra

D. Epididymis        IV. Sperm formation

1. A-IV, B-II, C-III, D-I

2. A-II, B-IV, C-I, D-III

3. A-I, B-III, C-IV, D-II

4. A-III, B-I, C-II, D-IV

Explanation:

Seminiferous tubules are the site of sperm formation, rete testis connects these tubules to vasa efferentia, epididymis is where sperm mature, and vas deferens transports them toward the urethra. The correct match is A-IV, B-II, C-III, D-I. Answer: Option 1

6. The function of vasa efferentia is to:

1. Store sperms

2. Transport sperms from rete testis to epididymis

3. Secrete testosterone

4. Produce seminal plasma

Explanation:

Vasa efferentia are fine tubules connecting the rete testis to the epididymis. They help transport sperms and absorb excess testicular fluid, aiding in sperm concentration. Their ciliated lining assists in gentle sperm movement. Answer: Option 2

7. Choose the correct statements:

Statement I: Urethra in males serves as a common passage for urine and semen.

Statement II: The urethra opens through the glans penis by the urethral meatus.

1. Only Statement I is correct

2. Only Statement II is correct

3. Both Statements are correct

4. Both Statements are incorrect

Explanation:

The male urethra is a common passage for semen and urine, running through the penis and opening at the urethral meatus. It plays a dual role in the excretory and reproductive systems. Thus, both statements are correct. Answer: Option 3

8. Which of the following cells nourish developing spermatogenic cells?

1. Leydig cells

2. Sertoli cells

3. Spermatogonia

4. Spermatocytes

Explanation:

Sertoli cells are large supporting cells in seminiferous tubules that provide nutrients and hormonal signals for developing sperm. They also form the blood-testis barrier and secrete inhibin to regulate spermatogenesis. Answer: Option 2

9. Which hormone stimulates Leydig cells to produce testosterone?

1. FSH

2. LH

3. GnRH

4. Prolactin

Explanation:

Luteinizing hormone (LH), secreted by the anterior pituitary, stimulates Leydig cells in the testes to produce testosterone. Testosterone regulates spermatogenesis, male secondary sexual characters, and reproductive functions. Answer: Option 2

10. Which structure connects each testis to the scrotal wall and helps in descent during development?

1. Vas deferens

2. Spermatic cord

3. Gubernaculum

4. Epididymis

Explanation:

The gubernaculum is a fibrous cord that guides the descent of testes from the abdominal cavity into the scrotum during fetal development. It helps anchor the testes to the scrotal base after descent. Answer: Option 3 

Topic: Spermatogenesis; Subtopic: Hormonal regulation of spermatogenesis

Keyword Definitions:

• GnRH: Gonadotropin Releasing Hormone secreted by the hypothalamus that regulates FSH and LH release from the pituitary.

• FSH: Follicle Stimulating Hormone stimulates Sertoli cells for spermatogenesis.

• LH: Luteinizing Hormone acts on Leydig cells to produce testosterone.

• Leydig Cells: Interstitial cells in testes producing testosterone.

• Sertoli Cells: Supportive cells in seminiferous tubules aiding spermatogenesis and nourishment of sperm cells.

• Spermiogenesis: Process of transformation of spermatids into mature spermatozoa.

• Spermatogenesis: Sequence of events by which spermatogonia transform into spermatozoa.

Lead Question – 2024
Identify the correct option (A), (B), (C), (D) with respect to spermatogenesis:

GnRH → LH → Factors → B → Androgens → Formation of spermatids
A → C → Factors → D

(1) ICSH, Interstitial cells, Leyding cells, spermiogenesis
(2) FSH, Sertoli cells, Leydig cells, spermatogenesis
(3) ICSH, Leydig cells, Sertoli cells, spermatogenesis
(4) FSH, Leyding cells, Sertoli cells, Spermiogenesis

Explanation: The hypothalamus releases GnRH which stimulates the anterior pituitary to secrete FSH and LH. LH (ICSH in males) acts on Leydig cells to release androgens, while FSH acts on Sertoli cells to promote spermatogenesis. Hence, the correct sequence is FSH → Leydig cells → Sertoli cells → Spermiogenesis. Answer: (4)

Guessed Questions:

1. Which hormone stimulates Leydig cells to produce testosterone?
(1) FSH
(2) LH
(3) Prolactin
(4) ACTH
Explanation: LH, also called Interstitial Cell Stimulating Hormone (ICSH) in males, acts on Leydig cells to stimulate testosterone production necessary for spermatogenesis and male secondary sexual characters. Answer: (2)

2. Which cells provide nourishment to developing sperms in seminiferous tubules?
(1) Leydig cells
(2) Sertoli cells
(3) Spermatogonia
(4) Spermatids
Explanation: Sertoli cells, present inside seminiferous tubules, provide structural and nutritional support to developing sperm cells and help in the process of spermatogenesis. Answer: (2)

3. The process of transformation of spermatids into spermatozoa is called:
(1) Spermatogenesis
(2) Spermiation
(3) Spermiogenesis
(4) Oogenesis
Explanation: Spermiogenesis is the final stage of spermatogenesis in which haploid spermatids undergo structural changes to form motile, mature spermatozoa. Answer: (3)

4. Which of the following hormones acts on Sertoli cells?
(1) LH
(2) FSH
(3) Testosterone
(4) Progesterone
Explanation: FSH directly stimulates Sertoli cells in the seminiferous tubules, promoting spermatogenesis and production of androgen-binding protein, which maintains testosterone levels for sperm maturation. Answer: (2)

5. In males, ICSH is another name for:
(1) LH
(2) FSH
(3) Prolactin
(4) Oxytocin
Explanation: ICSH (Interstitial Cell Stimulating Hormone) is the term used for LH in males. It stimulates Leydig cells to secrete testosterone, which regulates spermatogenesis and male reproductive physiology. Answer: (1)

6. Testosterone secretion is regulated by:
(1) FSH
(2) LH
(3) Estrogen
(4) Inhibin
Explanation: LH, also called ICSH, regulates testosterone secretion from Leydig cells. Testosterone plays a key role in sperm formation, growth of reproductive tissues, and development of secondary sexual traits. Answer: (2)

Assertion-Reason Question
Assertion (A): Testosterone is essential for spermatogenesis.
Reason (R): Testosterone stimulates Sertoli cells to release inhibin.
(1) Both A and R are true, and R is the correct explanation of A
(2) Both A and R are true, but R is not the correct explanation of A
(3) A is true, but R is false
(4) A is false, but R is true
Explanation: Testosterone is crucial for spermatogenesis as it maintains structural integrity of seminiferous tubules and promotes sperm formation. Inhibin, however, is secreted by Sertoli cells to inhibit FSH secretion. Answer: (2)

Matching Type Question
Match List I with List II:
A. FSH → I. Leydig cells
B. LH → II. Sertoli cells
C. Testosterone → III. Secondary sexual traits
D. Inhibin → IV. Regulates FSH secretion
(1) A–II, B–I, C–III, D–IV
(2) A–I, B–II, C–IV, D–III
(3) A–II, B–III, C–I, D–IV
(4) A–III, B–II, C–IV, D–I
Explanation: FSH acts on Sertoli cells, LH on Leydig cells, testosterone develops secondary sexual characteristics, and inhibin from Sertoli cells inhibits FSH secretion. Answer: (1)

Fill in the Blanks Question
During spermatogenesis, spermatogonia undergo ______ to form spermatocytes.
(1) Meiosis I
(2) Mitosis
(3) Meiosis II
(4) Cleavage
Explanation: Spermatogonia are diploid cells that undergo mitotic division to form primary spermatocytes which then enter meiosis to produce haploid spermatids. Answer: (2)

Choose the Correct Statements Question
Statement I: Spermiogenesis occurs in epididymis.
Statement II: Spermiation involves release of mature sperms into the lumen.
(1) Both statements are correct
(2) Both statements are incorrect
(3) Statement I is correct, Statement II is incorrect
(4) Statement I is incorrect, Statement II is correct
Explanation: Spermiogenesis occurs within seminiferous tubules, while spermiation is the release of mature spermatozoa from Sertoli cells into the lumen of seminiferous tubules. Answer: (4)

Topic: Female Reproductive System; Subtopic: Structure and Parts of Fallopian Tube

Keyword Definitions:

• Fallopian tube: A pair of muscular tubes that transport ova from the ovaries to the uterus and serve as the site of fertilization.

• Infundibulum: Funnel-shaped opening near the ovary with finger-like fimbriae that collect the ovum after ovulation.

• Ampulla: The widest and longest part of the fallopian tube where fertilization usually occurs.

• Isthmus: Narrow region that connects the ampulla to the uterus.

• Uterine fundus: Upper dome-shaped portion of the uterus, not part of the fallopian tube.

Lead Question – 2024
Which of the following is not a component of Fallopian tube?
(1) Isthmus
(2) Infundibulum
(3) Ampulla
(4) Uterine fundus
Explanation: The fallopian tube has four parts – infundibulum, ampulla, isthmus, and intramural (uterine) part. The uterine fundus, however, is a part of the uterus, not the fallopian tube. Therefore, the correct answer is (4) Uterine fundus. Fertilization occurs in the ampulla, while the ovum is received by fimbriae of the infundibulum.

Guessed Questions:

1. The fertilization in humans normally occurs in which part of the female reproductive tract?
(1) Isthmus
(2) Ampulla
(3) Infundibulum
(4) Uterus
Explanation: Fertilization typically takes place in the ampulla, which is the widest part of the fallopian tube. It provides an ideal environment for sperm-egg interaction. The ampulla connects the infundibulum to the isthmus and supports early zygotic development before implantation. Hence, the correct answer is (2) Ampulla, where the fusion of gametes usually occurs.

2. The fimbriae of the fallopian tube help in:
(1) Fertilization
(2) Movement of sperm
(3) Collection of ovum after ovulation
(4) Attachment of embryo
Explanation: Fimbriae are finger-like projections present at the margin of the infundibulum. They sweep over the ovary and help collect the ovum into the fallopian tube after ovulation. This ensures successful transport toward the site of fertilization. Hence, the correct answer is (3) Collection of ovum after ovulation by fimbriae.

3. Which part of the fallopian tube opens into the peritoneal cavity?
(1) Infundibulum
(2) Ampulla
(3) Isthmus
(4) Uterine part
Explanation: The infundibulum is the funnel-shaped distal part of the fallopian tube that opens into the peritoneal cavity near the ovary. It possesses fimbriae that catch the released ovum. This structure ensures a direct passage from the ovary into the reproductive tract. Hence, the correct answer is (1) Infundibulum, which opens into the peritoneal cavity.

4. Which of the following parts connects the fallopian tube to the uterus?
(1) Ampulla
(2) Infundibulum
(3) Isthmus
(4) Fimbriae
Explanation: The isthmus is the narrow and thick-walled portion of the fallopian tube that connects the ampulla to the uterus. It serves as a passage for the fertilized egg to reach the uterine cavity for implantation. Hence, the correct answer is (3) Isthmus, which forms the junction between the tube and the uterus.

5. The part of the fallopian tube closest to the ovary is:
(1) Isthmus
(2) Ampulla
(3) Infundibulum
(4) Uterine part
Explanation: The infundibulum is located closest to the ovary and is equipped with fimbriae to catch the ovum released from the ovarian follicle. This part ensures proper transport into the ampulla, where fertilization occurs. Hence, the correct answer is (3) Infundibulum, the funnel-like ovarian end of the fallopian tube.

6. Which of the following structures does not belong to the female reproductive tract?
(1) Cervix
(2) Ampulla
(3) Isthmus
(4) Vas deferens
Explanation: The vas deferens is a male reproductive duct that transports sperm from the epididymis to the ejaculatory duct. All other options — cervix, ampulla, and isthmus — are parts of the female reproductive system. Therefore, the correct answer is (4) Vas deferens, which is not part of the female tract.

Assertion–Reason Type:
Assertion (A): Fertilization generally occurs in the ampulla of the fallopian tube.
Reason (R): The ampulla provides suitable conditions for the meeting of gametes.
(1) Both A and R are true, and R is the correct explanation of A
(2) Both A and R are true, but R is not the correct explanation of A
(3) A is true but R is false
(4) A is false but R is true
Explanation: The ampulla provides an optimal environment with appropriate pH, secretions, and ciliary movement for fertilization. Hence, both statements are true, and R correctly explains A. The correct answer is (1) Both A and R are true, and R is the correct explanation of A, describing natural fertilization conditions in humans.

Matching Type:
Match List I with List II
A. Infundibulum – I. Connects to uterus
B. Ampulla – II. Funnel-shaped, near ovary
C. Isthmus – III. Widest part, site of fertilization
D. Fimbriae – IV. Finger-like projections
(1) A-II, B-III, C-I, D-IV
(2) A-IV, B-I, C-II, D-III
(3) A-I, B-IV, C-III, D-II
(4) A-III, B-II, C-IV, D-I
Explanation: The infundibulum is funnel-shaped near the ovary, the ampulla is the widest part where fertilization occurs, the isthmus connects to the uterus, and the fimbriae are finger-like projections that collect ova. Hence, the correct answer is (1) A-II, B-III, C-I, D-IV, representing structural organization of the fallopian tube.

Fill in the Blanks:
The ________ connects the fallopian tube to the uterus.
(1) Ampulla
(2) Isthmus
(3) Infundibulum
(4) Fimbriae
Explanation: The isthmus is the narrow part of the fallopian tube that joins it to the uterus. It helps transport the fertilized ovum for implantation. Its muscular walls aid in peristaltic movement of the zygote. Hence, the correct answer is (2) Isthmus, which forms the link between the fallopian tube and uterus.

Choose the Correct Statements:
Statement I: The fallopian tubes are directly attached to the ovaries.
Statement II: Fimbriae help in collecting the ovum from the ovary.
(1) Both I and II are true
(2) Both I and II are false
(3) I is false but II is true
(4) I is true but II is false
Explanation: The fallopian tubes are not directly attached to the ovaries; instead, fimbriae at the infundibulum capture the ovum. Therefore, Statement I is false, and Statement II is true. Hence, the correct answer is (3) I is false but II is true, explaining the functional coordination between ovaries and fimbriae.

Topic: Female Reproductive System; Subtopic: Hymen and its Clinical Significance

Keyword Definitions:

• Hymen: A thin membrane partially covering the vaginal opening, which may get torn due to various activities, not just sexual intercourse.

• Virginity: A social term referring to the state of not having engaged in sexual intercourse; not a medically verifiable condition.

• Coitus: The sexual union between male and female involving penetration of the penis into the vagina.

• Vagina: A muscular tubular part of the female reproductive tract extending from the cervix to the external genitalia.

• Reproductive Health: A state of complete physical, mental, and social well-being concerning reproductive functions and processes.

Lead Question - 2024
Given below are two statements:
Statement I: The presence or absence of hymen is not a reliable indicator of virginity.
Statement II: The hymen is torn during the first coitus only.
In the light of the above statements, choose the correct answer from the options given below:
(1) Both Statement I and Statement II are false
(2) Statement I is true but Statement II is false
(3) Statement I is false but Statement II is true
(4) Both Statement I and Statement II are true

Explanation: The correct answer is (2). Hymen rupture can occur due to physical activities like cycling, sports, or tampon use, not necessarily during first intercourse. Hence, its absence does not indicate loss of virginity. The hymen may also remain intact even after coitus, making it an unreliable marker of sexual activity or purity assessment.

1. Which of the following statements about hymen is correct?
(1) It always ruptures during first coitus
(2) It is a muscular tissue
(3) It may tear due to several non-sexual activities
(4) It is located near the cervix
Explanation: The correct answer is (3). The hymen is a delicate membrane that may rupture due to physical activities such as running, horse riding, or inserting tampons. Its rupture is not exclusive to sexual intercourse. Thus, it cannot be taken as a medical or moral indicator of virginity in any female individual.

2. The hymen is part of which structure in the female reproductive system?
(1) Vulva
(2) Uterus
(3) Fallopian tube
(4) Ovary
Explanation: The correct answer is (1). The hymen forms part of the external genitalia known as the vulva, located at the vaginal opening. It serves no specific reproductive function but is often mistaken as an indicator of virginity. Anatomically, it is a mucous membrane with varying shapes and thickness among individuals.

3. Which of the following is not a function of the hymen?
(1) Protection of vaginal opening
(2) Facilitating sperm entry
(3) Acting as a partial barrier to infection
(4) Covering vaginal entrance during childhood
Explanation: The correct answer is (2). The hymen has no role in facilitating sperm entry. Its biological purpose is minimal, offering partial protection during early life. It has variable forms—annular, septate, or cribriform—and its rupture may occur naturally or due to non-sexual causes, disproving myths regarding its sexual relevance.

4. What is the correct position of the hymen in the female body?
(1) Between uterus and cervix
(2) Between vagina and vulva
(3) Between fallopian tube and uterus
(4) Between ovary and fimbriae
Explanation: The correct answer is (2). The hymen lies at the junction of the vagina and vulva, marking the external entrance of the vaginal canal. It has a small central opening for menstrual flow and secretions. Its rupture or elasticity varies, and it bears no medical or ethical significance regarding sexual behavior.

5. Which activity can cause hymen rupture besides sexual intercourse?
(1) Jogging
(2) Swimming
(3) Horse riding
(4) All of the above
Explanation: The correct answer is (4). The hymen may tear due to vigorous activities such as swimming, running, cycling, or sports. Such rupture is common among adolescent girls even without sexual contact. Therefore, its absence cannot be used to determine virginity, emphasizing the need for scientific understanding of female anatomy.

6. Assertion-Reason Type Question:
Assertion (A): Hymen is considered a marker of virginity in many cultures.
Reason (R): It always breaks during first sexual intercourse.
(1) Both A and R are true, and R is the correct explanation of A.
(2) Both A and R are true, but R is not the correct explanation of A.
(3) A is true, but R is false.
(4) Both A and R are false.
Explanation: The correct answer is (3). Hymen is culturally misinterpreted as a symbol of virginity. However, its rupture may result from many non-sexual causes, and it may also remain intact after coitus. This proves that such beliefs are social constructs lacking anatomical or physiological basis.

7. Matching Type Question:
Match the following terms with their correct descriptions:
A. Hymen  I. Membrane partially covering vaginal opening
B. Vulva  II. External genital structure in females
C. Vagina  III. Canal for menstrual flow and childbirth
D. Cervix  IV. Narrow lower part of uterus
(1) A-I, B-II, C-III, D-IV
(2) A-II, B-I, C-IV, D-III
(3) A-III, B-IV, C-II, D-I
(4) A-IV, B-I, C-II, D-III
Explanation: The correct answer is (1). The hymen covers the vaginal opening, the vulva includes external genitals, the vagina serves as the passage for menstruation and childbirth, and the cervix connects uterus and vagina. Together, they form crucial parts of the female reproductive anatomy essential for various reproductive processes.

8. Fill in the Blanks:
The hymen may remain ________ even after repeated sexual intercourse and may get torn by ________.
(1) intact, non-sexual activities
(2) ruptured, ovulation
(3) thickened, fertilization
(4) regenerated, pregnancy
Explanation: The correct answer is (1). The hymen can remain intact after intercourse and may tear due to sports or physical strain. Its elasticity and thickness vary widely among individuals, and therefore, it cannot be used as a determinant for assessing sexual history or physical purity.

9. Which of the following statements about virginity is correct?
(1) It can be medically determined
(2) It depends solely on hymen rupture
(3) It is a social concept, not a medical fact
(4) It relates to hormonal changes in puberty
Explanation: The correct answer is (3). Virginity is a cultural and social concept with no medical or biological definition. Medical science recognizes no physiological sign that confirms virginity. The presence or absence of hymen has no relevance to personal worth or sexual activity.

10. Choose the Correct Statements:
Statement I: Hymen has variations in structure and elasticity among females.
Statement II: All women have a hymen of the same thickness and form.
(1) Both statements are true.
(2) Both statements are false.
(3) Statement I is true, Statement II is false.
(4) Statement I is false, Statement II is true.
Explanation: The correct answer is (3). The hymen varies in thickness, elasticity, and shape among individuals—annular, septate, or cribriform. Its variation is normal and unrelated to sexual behavior. Hence, generalizations about hymen structure are scientifically inaccurate and socially misleading.

Topic: Hormonal Regulation of Reproductive System; Subtopic: Role of Gonadotropins in Males and Females

Keyword Definitions:
• FSH (Follicle Stimulating Hormone): A pituitary hormone that stimulates follicle growth in females and spermatogenesis in males.
• LH (Luteinizing Hormone): A pituitary hormone stimulating ovulation in females and testosterone secretion in males.
• Ovarian Follicles: Structures in the ovary where oocytes mature.
• Leydig Cells: Interstitial cells of testes that secrete testosterone under LH stimulation.
• Estrogen: A female sex hormone secreted by ovarian follicles that regulates the menstrual cycle and secondary sexual characteristics.

Lead Question – 2024
Given below are two statements: one is labelled as Assertion A and the other as Reason R.

Assertion (A): FSH acts upon ovarian follicles in female and Leydig cells in male.
Reason (R): Growing ovarian follicles secrete estrogen in female while interstitial cells secrete androgen in male human being.

Choose the correct answer from the options given below:
(1) Both A and R are true but R is NOT the correct explanation of A
(2) A is true but R is false
(3) A is false but R is true
(4) Both A and R are true and R is the correct explanation of A

Explanation: The correct answer is (3) A is false but R is true. FSH acts on ovarian follicles in females and Sertoli cells in males, not on Leydig cells. Leydig cells are stimulated by LH to secrete androgens. However, the Reason is true because ovarian follicles secrete estrogen and interstitial cells secrete androgens.

1. Which hormone stimulates Leydig cells in males to secrete testosterone?
(1) LH
(2) FSH
(3) Prolactin
(4) Oxytocin

Explanation: The correct answer is (1) LH. Luteinizing hormone, secreted by the anterior pituitary, acts directly on Leydig cells located in the testes to produce testosterone, which supports spermatogenesis and development of male secondary sexual characters.

2. FSH in females is responsible for:
(1) Ovulation
(2) Growth and maturation of ovarian follicles
(3) Formation of corpus luteum
(4) Secretion of progesterone

Explanation: The correct answer is (2). FSH stimulates the growth and maturation of ovarian follicles during the follicular phase of the menstrual cycle, preparing them for ovulation. It also induces estrogen secretion by granulosa cells, essential for endometrial proliferation.

3. Which cells in the seminiferous tubules respond to FSH in males?
(1) Leydig cells
(2) Sertoli cells
(3) Spermatogonia
(4) Spermatids

Explanation: The correct answer is (2) Sertoli cells. FSH binds to receptors on Sertoli cells, stimulating spermatogenesis and the secretion of androgen-binding proteins that help maintain high testosterone levels in the seminiferous tubules for sperm development.

4. Which hormone primarily regulates ovulation in females?
(1) FSH
(2) LH
(3) Estrogen
(4) Progesterone

Explanation: The correct answer is (2) LH. The mid-cycle surge of LH triggers the rupture of the mature Graafian follicle, releasing the secondary oocyte into the fallopian tube, an event known as ovulation, followed by corpus luteum formation.

5. Which of the following hormones is secreted by corpus luteum?
(1) Estrogen
(2) Progesterone
(3) LH
(4) FSH

Explanation: The correct answer is (2) Progesterone. After ovulation, the ruptured follicle transforms into the corpus luteum, which secretes progesterone to maintain the uterine lining and support potential implantation during early pregnancy.

6. Which statement is correct regarding hormone action in reproduction?
(1) LH stimulates Sertoli cells
(2) FSH acts on Leydig cells
(3) LH acts on Leydig cells
(4) Estrogen acts on Sertoli cells

Explanation: The correct answer is (3). LH stimulates Leydig cells in testes to produce testosterone, essential for spermatogenesis. FSH acts on Sertoli cells, not Leydig cells, to promote sperm maturation. Estrogen has no direct role in male spermatogenesis.

7. Assertion-Reason Type:
Assertion (A): LH is responsible for ovulation in females.
Reason (R): LH surge causes the rupture of Graafian follicle releasing the ovum.
(1) Both A and R are true and R is the correct explanation of A
(2) Both A and R are true but R is not the correct explanation of A
(3) A is true but R is false
(4) A is false but R is true

Explanation: The correct answer is (1). LH surge triggers ovulation by rupturing the mature follicle. This event marks the transition from the follicular to the luteal phase, with progesterone production beginning post-ovulation.

8. Matching Type:
Match the following hormones with their respective functions:

A. FSH — I. Follicular growth
B. LH — II. Ovulation
C. Estrogen — III. Endometrial proliferation
D. Progesterone — IV. Maintenance of pregnancy

(1) A-I, B-II, C-III, D-IV
(2) A-II, B-I, C-IV, D-III
(3) A-III, B-IV, C-I, D-II
(4) A-IV, B-III, C-II, D-I

Explanation: The correct answer is (1). FSH promotes follicular growth, LH induces ovulation, estrogen stimulates endometrial proliferation, and progesterone maintains the uterine lining for implantation and early pregnancy.

9. Fill in the Blanks:
In males, LH acts on __________ cells to stimulate the production of testosterone.
(1) Sertoli
(2) Leydig
(3) Spermatogenic
(4) Granulosa

Explanation: The correct answer is (2) Leydig. LH binds to receptors on Leydig cells in the testes, stimulating them to produce testosterone, which supports spermatogenesis and the development of male secondary sexual characteristics.

10. Choose the Correct Statements:
Statement I: FSH acts on Sertoli cells in males to promote spermatogenesis.
Statement II: LH stimulates Leydig cells to secrete testosterone.
(1) Both I and II are true
(2) Both I and II are false
(3) I is true but II is false
(4) I is false but II is true

Explanation: The correct answer is (1). FSH and LH coordinate male reproductive functions. FSH regulates spermatogenesis through Sertoli cells, while LH controls testosterone synthesis via Leydig cells, ensuring hormonal balance for sperm production and maturation.

Topic: Lactation and Maternal Care; Subtopic: Importance of Colostrum and Breastfeeding

Keyword Definitions:
• Breastfeeding: The process of feeding an infant with milk produced from the mother’s mammary glands.
• Colostrum: The first yellowish milk produced after childbirth, rich in antibodies and proteins essential for newborn immunity.
• Antibodies: Immune proteins that protect the infant from infections by neutralizing pathogens.
• Immunity: The ability of the body to resist harmful microorganisms and toxins.
• Lactation: The process of milk secretion from the mammary glands, stimulated by prolactin and oxytocin.

Lead Question – 2024
Given below are two statements:

Assertion (A): Breast-feeding during the initial period of infant growth is recommended by doctors for bringing a healthy baby.
Reason (R): Colostrum contains several antibodies absolutely essential to develop resistance for the newborn baby.

Choose the most appropriate answer from the options given below:
(1) Both A and R are correct but R is NOT the correct explanation of A
(2) A is correct but R is not correct
(3) A is not correct but R is correct
(4) Both A and R are correct and R is the correct explanation of A

Explanation: The correct answer is (4). Both A and R are correct, and R correctly explains A. Breastfeeding is highly recommended as colostrum provides passive immunity, rich in IgA, proteins, and growth factors that protect infants from infections. It also aids intestinal development and provides emotional bonding between mother and child.

1. Which hormone is responsible for milk ejection during lactation?
(1) Prolactin
(2) Oxytocin
(3) Estrogen
(4) Progesterone

Explanation: The correct answer is (2) Oxytocin. While prolactin stimulates milk production, oxytocin released from the posterior pituitary gland causes contraction of myoepithelial cells around alveoli, ejecting milk into ducts. This reflex is initiated by the baby’s suckling and emotional bonding between mother and child.

2. The first milk secreted by the mother after childbirth is known as:
(1) Lactose
(2) Colostrum
(3) Albumin
(4) Casein

Explanation: The correct answer is (2) Colostrum. It is yellowish and thick, produced in the first few days postpartum. Colostrum contains antibodies, especially IgA, essential proteins, and immune cells that help build the newborn’s immunity and protect against respiratory and intestinal infections.

3. Which antibody is predominantly present in colostrum?
(1) IgG
(2) IgA
(3) IgM
(4) IgE

Explanation: The correct answer is (2) IgA. Secretory IgA present in colostrum forms a protective coating on the infant’s mucous membranes, preventing pathogens from entering tissues. It provides passive immunity during the initial months when the infant’s immune system is immature.

4. Which of the following hormones maintains lactation in a mother after delivery?
(1) LH
(2) FSH
(3) Prolactin
(4) Thyroxine

Explanation: The correct answer is (3) Prolactin. Secreted by the anterior pituitary, prolactin stimulates the mammary glands to synthesize milk. Its secretion is maintained by the baby’s suckling reflex, ensuring continuous milk production throughout lactation.

5. Breast milk is considered superior to cow’s milk for newborns because:
(1) It has more fat content
(2) It contains antibodies and immune cells
(3) It has less lactose
(4) It is easier to digest due to enzymes

Explanation: The correct answer is (2). Breast milk provides essential antibodies, particularly IgA, that protect infants from infections. It also contains digestible fats, lactalbumin, and enzymes like lipase and lysozyme, enhancing nutrition and immunity, unlike cow’s milk which lacks adequate immune factors.

6. Which hormone stimulates the development of mammary glands during pregnancy?
(1) Estrogen and progesterone
(2) FSH and LH
(3) Oxytocin and relaxin
(4) Prolactin and thyroxine

Explanation: The correct answer is (1) Estrogen and progesterone. Estrogen stimulates ductal growth, while progesterone promotes alveolar and lobular development. These hormones prepare the mammary glands for lactation, though actual milk secretion begins after childbirth when their levels drop.

7. Assertion–Reason Type:
Assertion (A): Breast milk provides passive immunity to the infant.
Reason (R): It contains immunoglobulins and lymphocytes that fight infections.
(1) Both A and R are true, and R is the correct explanation of A
(2) Both A and R are true, but R is not the correct explanation of A
(3) A is true but R is false
(4) A is false but R is true

Explanation: The correct answer is (1). Both statements are true, and R correctly explains A. Breast milk contains IgA, macrophages, and lymphocytes that provide passive immunity, protecting infants from diseases until their immune system becomes fully functional.

8. Matching Type:
Match the following hormones with their functions:

A. Prolactin — I. Milk production
B. Oxytocin — II. Milk ejection
C. Estrogen — III. Growth of ducts
D. Progesterone — IV. Alveolar development

(1) A-I, B-II, C-III, D-IV
(2) A-II, B-I, C-IV, D-III
(3) A-III, B-IV, C-I, D-II
(4) A-IV, B-III, C-II, D-I

Explanation: The correct answer is (1). Prolactin stimulates milk production, oxytocin triggers milk ejection, estrogen promotes ductal development, and progesterone aids alveolar maturation, ensuring coordinated preparation of mammary glands for lactation and feeding.

9. Fill in the Blanks:
The first milk secreted after childbirth, rich in antibodies, is called __________.
(1) Casein
(2) Colostrum
(3) Whey
(4) Albumin

Explanation: The correct answer is (2) Colostrum. It is yellowish, protein-rich, and packed with immunoglobulins, especially IgA. It strengthens the newborn’s immune system, enhances gut health, and provides essential nutrients immediately after birth.

10. Choose the Correct Statements:
Statement I: Colostrum is rich in proteins and antibodies.
Statement II: It is secreted before delivery and helps in immunity development.
(1) Both I and II are true
(2) Both I and II are false
(3) I is true but II is false
(4) I is false but II is true

Explanation: The correct answer is (3). Colostrum is indeed rich in proteins and antibodies, but it is secreted after delivery, not before. It provides passive immunity, prevents infections, and is vital for the infant’s initial immune protection and nutrition.

Topic: Oogenesis and Follicular Development; Subtopic: Follicle Maturation and Ovulation

Keyword Definitions:

• Oogenesis: The process of formation and development of female gametes (ova) in the ovary.

• Primary Follicle: Early stage ovarian follicle with oocyte surrounded by a single layer of granulosa cells.

• Secondary Follicle: Follicle in which the oocyte is surrounded by multiple layers of granulosa cells, theca, and a fluid-filled cavity called antrum.

• Graafian Follicle: Mature ovarian follicle ready to release the secondary oocyte during ovulation.

• Ovulation: The process by which a mature oocyte is released from the ovary.

• Granulosa Cells: Somatic cells surrounding the oocyte, providing nutrients and hormonal support.

• Theca: Connective tissue layer surrounding granulosa cells, contributing to steroid hormone synthesis.

• Antrum: Fluid-filled cavity within a secondary follicle.

• Secondary Oocyte: Haploid cell resulting from the first meiotic division in oogenesis, released during ovulation.

• Follicular Development: Sequential maturation of ovarian follicles from primary to secondary to Graafian stage.

• Maturation: The process of follicle and oocyte reaching full functional and structural readiness for ovulation.

Lead Question - 2023 (Manipur)

Given below are two statements regarding oogenesis:

I: The primary follicles get surrounded by more layers of granulosa cells, a theca and shows fluid filled cavity antrum. Now it is called secondary follicle.

II: Graafian follicle ruptures to release the secondary oocyte from the ovary by the process called ovulation.

In the light of the above statements, choose the correct answer from the options given below:

1. Statement I is correct but Statement II is false

2. Statement I is incorrect but Statement II is true

3. Both Statement I and Statement II are true

4. Both Statement I and Statement II are false

Explanation:

Statement I is correct: the primary follicle develops multiple layers of granulosa cells, a theca, and a fluid-filled antrum to form a secondary follicle. Statement II is correct: the Graafian follicle ruptures during ovulation, releasing the secondary oocyte from the ovary into the fallopian tube. Both statements accurately describe the stages of oogenesis and follicular development, highlighting the structural and functional changes during maturation. Correct option is 3.

1. Single Correct Answer MCQ:

Which structure in oogenesis contains the fluid-filled antrum?

1. Primary follicle

2. Secondary follicle

3. Graafian follicle

4. Primordial follicle

Explanation:

The secondary follicle is characterized by multiple layers of granulosa cells, a theca, and a fluid-filled antrum. Primary and primordial follicles do not have an antrum, and the Graafian follicle is the mature stage following secondary follicle. Correct answer is 2.

2. Single Correct Answer MCQ:

Ovulation releases which of the following?

1. Primary oocyte

2. Secondary oocyte

3. Polar body

4. Zygote

Explanation:

During ovulation, the Graafian follicle ruptures, releasing the secondary oocyte into the fallopian tube for potential fertilization. Primary oocyte is arrested in prophase I, polar body is byproduct, zygote forms after fertilization. Correct answer is 2.

3. Single Correct Answer MCQ:

Which layer surrounds the granulosa cells and contributes to hormone synthesis?

1. Antrum

2. Theca

3. Zona pellucida

4. Follicular fluid

Explanation:

The theca layer surrounds granulosa cells and produces steroid hormones essential for follicle maturation. Antrum is fluid cavity, zona pellucida surrounds oocyte, follicular fluid fills antrum. Correct answer is 2.

4. Single Correct Answer MCQ:

The Graafian follicle is also called:

1. Primary follicle

2. Secondary follicle

3. Mature follicle

4. Primordial follicle

Explanation:

The Graafian follicle is the mature, pre-ovulatory follicle containing a secondary oocyte ready for ovulation. It follows the secondary follicle stage. Correct answer is 3.

5. Single Correct Answer MCQ:

Which process occurs after rupture of the Graafian follicle?

1. Fertilization

2. Ovulation

3. Meiosis I

4. Antrum formation

Explanation:

Ovulation occurs when the Graafian follicle ruptures, releasing the secondary oocyte into the fallopian tube. Fertilization occurs afterward, meiosis I is earlier, and antrum forms in secondary follicle. Correct answer is 2.

6. Single Correct Answer MCQ:

Which cells provide nutrient and hormonal support to the developing oocyte?

1. Theca cells

2. Granulosa cells

3. Polar bodies

4. Zygote

Explanation:

Granulosa cells surround the oocyte in follicles and provide nutrients and hormonal signals necessary for oocyte maturation. Theca cells contribute to steroidogenesis, polar bodies are byproducts, zygote forms after fertilization. Correct answer is 2.

7. Assertion-Reason MCQ:

Assertion (A): The secondary follicle has a fluid-filled cavity called antrum.

Reason (R): The antrum forms due to accumulation of follicular fluid between granulosa cells.

1. Both A and R are true and R explains A

2. Both A and R are true but R does not explain A

3. A is true but R is false

4. Both A and R are false

Explanation:

The antrum forms in the secondary follicle as fluid accumulates between granulosa cells. Both statements are correct, and R explains A. Correct answer is 1.

8. Matching Type MCQ:

Match follicle stages with characteristics:

A. Primary follicle — (i) Single layer granulosa cells

B. Secondary follicle — (ii) Antrum formation

C. Graafian follicle — (iii) Mature pre-ovulatory

D. Primordial follicle — (iv) Dormant oocyte

1. A-(i), B-(ii), C-(iii), D-(iv)

2. A-(ii), B-(i), C-(iv), D-(iii)

3. A-(iii), B-(iv), C-(ii), D-(i)

4. A-(iv), B-(iii), C-(i), D-(ii)

Explanation:

Correct matches: Primordial follicle → dormant oocyte, Primary follicle → single layer granulosa, Secondary follicle → antrum, Graafian follicle → mature pre-ovulatory follicle. Correct option is 1.

9. Fill in the Blanks MCQ:

The fluid-filled cavity in the secondary follicle is called ______.

1. Theca

2. Antrum

3. Zona pellucida

4. Polar body

Explanation:

The antrum is the fluid-filled cavity in a secondary follicle that supports oocyte maturation and hormone accumulation. Correct answer is 2.

10. Choose the correct statements MCQ:

Statement I: Ovulation releases the secondary oocyte.

Statement II: Primary follicle contains a single layer of granulosa cells.

1. Statement I only

2. Statement II only

3. Both statements are true

4. Both statements are false

Explanation:

Statement I is correct: ovulation releases the secondary oocyte from the Graafian follicle. Statement II is correct: primary follicle has a single layer of granulosa cells surrounding the oocyte. Hence, both statements are true. Correct answer is 3.

Topic: Gametogenesis and Hormonal Regulation; Subtopic: Hormonal Control of Spermatogenesis

Keyword Definitions:

• Gonadotropin: Hormones secreted by the anterior pituitary that regulate the function of gonads (FSH and LH).

• FSH (Follicle-Stimulating Hormone): Stimulates Sertoli cells and promotes spermiogenesis in males.

• LH (Luteinizing Hormone): Stimulates Leydig cells in testes to produce androgens like testosterone.

• GnRH (Gonadotropin-Releasing Hormone): Secreted from hypothalamus to regulate release of FSH and LH.

• Androgens: Male sex hormones responsible for spermatogenesis and development of secondary sexual characters.

• Spermatogenesis: Process of formation of sperm cells from spermatogonia.

• Spermiogenesis: Final maturation process of spermatids into spermatozoa.

Lead Question - 2023 (Manipur)

Arrange the sequence of different hormones for their role during gametogenesis:
A. Gonadotropin LH stimulates synthesis and secretion of Androgen
B. Gonadotropin releasing hormone from hypothalamus
C. Androgen stimulates spermatogenesis
D. Gonadotropin FSH helps in the process of spermiogenesis
E. Gonadotropins from anterior pituitary gland

Choose the correct answer from the options given below:

1. (E), (A), (D), (B), (C)
2. (C), (A), (D), (E), (B)
3. (B), (E), (A), (C), (D)
4. (D), (B), (A), (C), (E)

Explanation: The hormonal regulation of spermatogenesis begins with GnRH from the hypothalamus (B) which stimulates anterior pituitary (E) to secrete gonadotropins FSH and LH. LH (A) stimulates Leydig cells to secrete androgens that trigger spermatogenesis (C). FSH (D) helps in spermiogenesis. Hence, the correct sequence is (B), (E), (A), (C), (D).

Guessed Question 1: Which hormone stimulates Leydig cells to secrete testosterone?

1. FSH 2. LH 3. GnRH 4. Prolactin

Explanation: Luteinizing Hormone (LH) acts on Leydig cells in the testes to promote the synthesis and secretion of testosterone. Testosterone further stimulates spermatogenesis in seminiferous tubules. FSH acts on Sertoli cells, whereas GnRH from the hypothalamus regulates both FSH and LH release from the anterior pituitary gland.

Guessed Question 2: Which of the following is secreted by Sertoli cells?

1. Testosterone 2. Inhibin 3. LH 4. GnRH

Explanation: Sertoli cells secrete inhibin, a hormone that provides negative feedback to the anterior pituitary to regulate FSH secretion. They also help in nurturing developing spermatogenic cells and facilitate spermiogenesis. Testosterone is secreted by Leydig cells under LH stimulation from the anterior pituitary gland.

Guessed Question 3: FSH in males is primarily responsible for:

1. Development of secondary sexual characters
2. Spermatogenesis
3. Spermiogenesis
4. Testosterone secretion

Explanation: Follicle Stimulating Hormone (FSH) acts on Sertoli cells of the seminiferous tubules and promotes spermiogenesis — the final maturation of spermatids into spermatozoa. LH, on the other hand, acts on Leydig cells to produce testosterone. Thus, FSH’s role is crucial in sperm maturation and reproductive function.

Guessed Question 4: Which of the following acts as a feedback regulator of FSH secretion?

1. Inhibin 2. Testosterone 3. Progesterone 4. Estrogen

Explanation: Inhibin, produced by Sertoli cells in males, specifically inhibits FSH secretion from the anterior pituitary gland through a negative feedback mechanism. Testosterone regulates LH secretion, whereas inhibin selectively controls FSH levels, ensuring balanced spermatogenesis and hormonal control of male reproduction.

Guessed Question 5: Identify the correct sequence of spermatogenic stages:

1. Spermatid → Spermatogonia → Spermatozoa
2. Spermatogonia → Spermatocyte → Spermatid → Spermatozoa
3. Spermatocyte → Spermatogonia → Spermatid → Spermatozoa
4. Spermatogonia → Spermatid → Spermatocyte → Spermatozoa

Explanation: Spermatogenesis begins with spermatogonia which divide mitotically to form primary spermatocytes. These undergo meiosis to produce spermatids, which further differentiate into spermatozoa during spermiogenesis. Thus, the correct order of stages is Spermatogonia → Spermatocyte → Spermatid → Spermatozoa.

Guessed Question 6: Which of the following hormones is secreted by the hypothalamus?

1. GnRH 2. LH 3. FSH 4. Testosterone

Explanation: Gonadotropin-Releasing Hormone (GnRH) is secreted by the hypothalamus. It stimulates the anterior pituitary to release FSH and LH, which regulate testicular function. LH acts on Leydig cells, and FSH acts on Sertoli cells, together ensuring proper hormonal control of spermatogenesis in males.

Assertion-Reason Type Question:

Assertion (A): LH stimulates Leydig cells to produce testosterone.
Reason (R): Testosterone inhibits FSH secretion from the anterior pituitary.

1. Both A and R are true, and R is the correct explanation of A.
2. Both A and R are true, but R is not the correct explanation of A.
3. A is true, but R is false.
4. A is false, but R is true.

Explanation: LH indeed stimulates Leydig cells to produce testosterone, which provides negative feedback on LH secretion, not FSH. FSH is mainly regulated by inhibin from Sertoli cells. Hence, Assertion is true, but the Reason is false. The correct answer is option 3.

Matching Type Question:

Match the hormones with their function:
A. LH
B. FSH
C. Testosterone
D. Inhibin

1. Stimulates Sertoli cells
2. Regulates secondary sexual traits
3. Inhibits FSH
4. Stimulates Leydig cells

Codes: A-4, B-1, C-2, D-3

Explanation: LH acts on Leydig cells to promote testosterone secretion. FSH stimulates Sertoli cells to support spermatogenesis. Testosterone regulates male secondary sexual traits, and inhibin inhibits FSH. Correct matching is A-4, B-1, C-2, D-3.

Fill in the Blanks Type Question:

________ secreted from Sertoli cells provides negative feedback to control FSH secretion.

1. Testosterone 2. Inhibin 3. Estrogen 4. LH

Explanation: Inhibin is secreted by Sertoli cells and inhibits FSH secretion by acting on the anterior pituitary gland. This feedback mechanism maintains hormonal balance during spermatogenesis. Testosterone mainly regulates LH secretion, while estrogen has a minor role in males.

Choose the Correct Statements Type Question:

Statement I: FSH acts on Leydig cells to produce testosterone.
Statement II: LH acts on Leydig cells to produce testosterone.

1. Both statements are true.
2. Both statements are false.
3. Statement I is true, Statement II is false.
4. Statement I is false, Statement II is true.

Explanation: LH, not FSH, acts on Leydig cells to produce testosterone, which promotes spermatogenesis. FSH instead acts on Sertoli cells to assist in spermiogenesis and secretes inhibin. Therefore, Statement I is false and Statement II is true. The correct answer is option 4.

Subtopic: Hormonal Regulation of Gametogenesis

Keyword Definitions:

• Gametogenesis: The process by which male and female gametes (sperm and ova) are produced through meiosis and differentiation.

• LH (Luteinizing Hormone): Gonadotropin hormone from anterior pituitary stimulating testosterone production in males and ovulation in females.

• FSH (Follicle Stimulating Hormone): Gonadotropin that stimulates spermatogenesis in males and follicular development in females.

• GnRH (Gonadotropin Releasing Hormone): Hormone secreted by hypothalamus controlling the release of FSH and LH from anterior pituitary.

• Androgen: Male sex hormones like testosterone that stimulate spermatogenesis.

• Spermiogenesis: The final stage of spermatogenesis where spermatids differentiate into mature spermatozoa.

• Spermatogenesis: Process of formation of sperm cells from spermatogonia under hormonal control.

• Anterior Pituitary: Endocrine gland secreting FSH and LH essential for reproductive function.

Lead Question – 2023 (Manipur)

Arrange the sequence of different hormones for their role during gametogenesis:
A. Gonadotropin LH stimulates synthesis and secretion of Androgen
B. Gonadotropin releasing hormone from hypothalamus
C. Androgen stimulates spermatogenesis
D. Gonadotropin FSH helps in the process of spermiogenesis
E. Gonadotropins from anterior pituitary gland

Explanation: The sequence of hormonal events during gametogenesis starts with GnRH from hypothalamus (B), which stimulates gonadotropins release from anterior pituitary (E). LH specifically stimulates androgen synthesis (A), which promotes spermatogenesis (C). FSH helps in spermiogenesis (D). Correct sequential order of hormonal action is: B → E → A → C → D. This pathway ensures proper maturation of gametes through coordinated endocrine control. Correct answer: B, E, A, C, D.

1. Single Correct Answer MCQ:
Which hormone directly stimulates testosterone production in males?
1. FSH
2. LH
3. GnRH
4. Prolactin
Explanation: Luteinizing Hormone (LH) secreted by anterior pituitary stimulates Leydig cells in testes to produce testosterone, which is essential for spermatogenesis and secondary sexual characteristics. Correct answer: 2. LH.

2. Single Correct Answer MCQ:
FSH primarily supports which stage in male reproduction?
1. Spermatogenesis
2. Spermiogenesis
3. Androgen synthesis
4. Ovulation
Explanation: Follicle Stimulating Hormone (FSH) promotes the final maturation of spermatids into spermatozoa during spermiogenesis by acting on Sertoli cells. Correct answer: 2. Spermiogenesis.

3. Single Correct Answer MCQ:
Which hormone is secreted by hypothalamus to regulate pituitary gonadotropins?
1. Testosterone
2. FSH
3. LH
4. GnRH
Explanation: Gonadotropin Releasing Hormone (GnRH) from hypothalamus stimulates the anterior pituitary to release FSH and LH, regulating gametogenesis. Correct answer: 4. GnRH.

4. Single Correct Answer MCQ:
Androgens primarily act on:
1. Hypothalamus
2. Pituitary
3. Testes
4. Sertoli cells
Explanation: Androgens, mainly testosterone, act on the testes to promote spermatogenesis and on Sertoli cells indirectly, supporting sperm maturation and male secondary sexual characteristics. Correct answer: 3. Testes.

5. Single Correct Answer MCQ:
Which hormone triggers both FSH and LH secretion?
1. Testosterone
2. GnRH
3. Inhibin
4. Estrogen
Explanation: GnRH from hypothalamus stimulates anterior pituitary to secrete both FSH and LH, initiating gametogenesis and regulating male reproductive functions. Correct answer: 2. GnRH.

6. Single Correct Answer MCQ:
LH acts mainly on:
1. Sertoli cells
2. Leydig cells
3. Hypothalamus
4. Seminiferous tubules
Explanation: LH binds Leydig cells in the testes, stimulating androgen (testosterone) production crucial for spermatogenesis and male secondary sexual characteristics. Correct answer: 2. Leydig cells.

7. Assertion-Reason MCQ:
Assertion (A): GnRH stimulates anterior pituitary to release gonadotropins.
Reason (R): Gonadotropins directly act on hypothalamus.
1. Both A and R true, R explains A
2. Both A and R true, R does not explain A
3. A true, R false
4. A false, R true
Explanation: GnRH stimulates anterior pituitary to release FSH and LH. Gonadotropins act on gonads, not hypothalamus. Correct answer: 3. A true, R false.

8. Matching Type MCQ:
Match hormone with function:
A. GnRH – (i) Stimulates pituitary
B. LH – (ii) Androgen synthesis
C. FSH – (iii) Spermiogenesis
D. Androgen – (iv) Spermatogenesis
1. A–i, B–ii, C–iii, D–iv
2. A–i, B–iii, C–ii, D–iv
3. A–ii, B–i, C–iv, D–iii
4. A–iii, B–iv, C–i, D–ii
Explanation: GnRH stimulates pituitary, LH triggers androgen synthesis, FSH promotes spermiogenesis, Androgens stimulate spermatogenesis. Correct answer: 1.

9. Fill in the Blanks MCQ:
__________ from hypothalamus controls __________ and LH secretion, which in turn stimulates __________ production.
1. GnRH, FSH, androgen
2. FSH, GnRH, estrogen
3. LH, GnRH, testosterone
4. Androgen, LH, GnRH
Explanation: GnRH from hypothalamus stimulates FSH and LH release from pituitary; LH then triggers androgen production in Leydig cells. Correct answer: 1.

10. Choose the Correct Statements MCQ:
Statement I: FSH helps in spermiogenesis.
Statement II: Androgen stimulates spermatogenesis.
1. Both true
2. Both false
3. I true, II false
4. I false, II true
Explanation: FSH acts on Sertoli cells to promote spermiogenesis; Androgens stimulate spermatogenesis in testes. Both statements are correct. Correct answer: 1.

Topic: Endocrine System; Subtopic: Thyroid Hormone Functions

Keyword Definitions:
Thyroid hormone: Hormones produced by the thyroid gland, mainly thyroxine (T4) and triiodothyronine (T3), regulating metabolism.
Basal metabolic rate (BMR): The rate of energy expenditure of the body at rest.
Sleep-wake cycle: Circadian rhythm regulating periods of sleep and wakefulness.
Water and electrolyte balance: Regulation of fluid and ion concentrations in body.
RBC formation: Production of red blood cells, also called erythropoiesis.
Metabolism: Chemical processes maintaining life and energy production.
Endocrine control: Hormonal regulation of physiological processes.
Triiodothyronine (T3): Active thyroid hormone regulating growth and metabolism.
Thyroxine (T4): Precursor of T3, regulates metabolic activity.
Homeostasis: Maintenance of stable internal environment.
Hormone deficiency: Inadequate secretion of a hormone affecting body function.

Lead Question (2023):
Which of the following are NOT under the control of thyroid hormone?
A. Maintenance of water and electrolyte balance
B. Regulation of basal metabolic rate
C. Normal rhythm of sleep-wake cycle
D. Support the process of RBC formation
Choose the correct answer from the options given below:
(1) C and D only
(2) D and E only
(3) A and D only
(4) B and C only

Answer & Explanation: Option 3 is correct. Thyroid hormones regulate basal metabolic rate, energy expenditure, and growth, but they do not directly control water-electrolyte balance (regulated by ADH, aldosterone) or RBC formation (regulated primarily by erythropoietin). Sleep-wake cycles are influenced by melatonin and circadian rhythms. Understanding the specific physiological roles of thyroid hormones is critical in endocrinology, for diagnosing hypo- or hyperthyroidism, and differentiating hormonal effects from those of other endocrine glands in maintaining overall homeostasis in the body.

1. Single Correct Answer MCQ: Which hormone primarily regulates basal metabolic rate?
A) Thyroid hormone
B) Insulin
C) Cortisol
D) Growth hormone

Answer & Explanation: Option A is correct. Thyroid hormones (T3 and T4) increase basal metabolic rate by enhancing oxygen consumption, protein synthesis, and energy production. Insulin regulates glucose metabolism, cortisol affects stress response, and growth hormone influences growth and tissue repair. Proper thyroid function is crucial for energy homeostasis, thermogenesis, and maintaining normal metabolism in all tissues.

2. Single Correct Answer MCQ: Excess thyroid hormone causes which condition?
A) Hypothyroidism
B) Hyperthyroidism
C) Addison's disease
D) Cretinism

Answer & Explanation: Option B is correct. Hyperthyroidism results from excessive thyroid hormone production, causing weight loss, increased metabolism, heat intolerance, tachycardia, and nervousness. Hypothyroidism is due to deficiency, Addison's disease affects adrenal glands, and cretinism results from congenital thyroid hormone deficiency. Understanding hormone excess or deficiency is key for diagnosing endocrine disorders and managing metabolism-related complications.

3. Single Correct Answer MCQ: Which gland secretes thyroid hormones?
A) Pituitary gland
B) Thyroid gland
C) Adrenal gland
D) Parathyroid gland

Answer & Explanation: Option B is correct. The thyroid gland secretes thyroxine (T4) and triiodothyronine (T3), regulating metabolism, growth, and development. Pituitary secretes TSH controlling thyroid function, adrenal glands secrete cortisol and aldosterone, and parathyroid regulates calcium levels. Correct identification of hormone sources is essential for understanding endocrine feedback mechanisms and managing related disorders effectively.

4. Single Correct Answer MCQ: Which of the following is a symptom of hypothyroidism?
A) Weight loss
B) Heat intolerance
C) Fatigue and cold intolerance
D) Tachycardia

Answer & Explanation: Option C is correct. Hypothyroidism decreases basal metabolic rate, causing fatigue, lethargy, cold intolerance, weight gain, and bradycardia. Weight loss and tachycardia are features of hyperthyroidism, and heat intolerance is associated with excessive thyroid hormone. Recognizing symptoms is vital for early diagnosis, appropriate hormone replacement therapy, and preventing complications like myxedema or growth retardation in children.

5. Single Correct Answer MCQ: Which hormone stimulates RBC formation indirectly?
A) Thyroid hormone
B) Erythropoietin
C) Cortisol
D) Parathyroid hormone

Answer & Explanation: Option B is correct. Erythropoietin, produced by kidneys, stimulates RBC production in bone marrow. Thyroid hormones enhance metabolism but do not directly induce erythropoiesis. Cortisol affects stress response, and parathyroid hormone regulates calcium. Understanding hormone specificity is crucial to distinguish metabolic regulation from hematopoietic control in physiology and clinical medicine.

6. Single Correct Answer MCQ: Which hormone regulates calcium and phosphorus metabolism?
A) Thyroid hormone
B) Parathyroid hormone
C) TSH
D) Calcitonin

Answer & Explanation: Option B is correct. Parathyroid hormone increases blood calcium by stimulating bone resorption and renal calcium reabsorption. Thyroid hormones regulate metabolism, TSH stimulates thyroid gland, and calcitonin lowers calcium. Knowledge of hormone-specific functions helps in diagnosing endocrine imbalances and managing bone, mineral, and metabolic disorders effectively.

7. Assertion-Reason MCQ:
Assertion (A): Thyroid hormone does not regulate water-electrolyte balance.
Reason (R): ADH and aldosterone primarily control water and sodium levels.
A) Both A and R are true and R is the correct explanation of A
B) Both A and R are true but R is not the correct explanation of A
C) A is true but R is false
D) A is false but R is true

Answer & Explanation: Option A is correct. Thyroid hormones influence metabolism and energy regulation but do not directly control water and electrolyte balance. ADH from the posterior pituitary and aldosterone from adrenal cortex regulate fluid and sodium homeostasis. Understanding distinct hormone roles is critical for differentiating endocrine feedback systems and clinical evaluation of disorders like dehydration, hyponatremia, or thyroid dysfunction.

8. Matching Type MCQ: Match hormones with primary function:
List I - List II
A. Thyroid hormone - I. Regulates metabolism
B. ADH - II. Regulates water balance
C. Aldosterone - III. Regulates sodium reabsorption
Choose correct option:
1) A-I, B-II, C-III
2) A-II, B-I, C-III
3) A-III, B-II, C-I
4) A-I, B-III, C-II

Answer & Explanation: Option 1 is correct. Thyroid hormone regulates metabolism (A-I), ADH controls water balance (B-II), and aldosterone regulates sodium reabsorption (C-III). Matching hormones to their specific physiological roles is essential to understand homeostasis, endocrine regulation, and the differentiation of metabolic versus electrolyte control mechanisms in clinical and physiological contexts.

9. Fill in the Blanks MCQ: The ________ gland secretes TSH which stimulates thyroid hormone release.
A) Thyroid
B) Pituitary
C) Adrenal
D) Parathyroid

Answer & Explanation: Option B is correct. TSH (Thyroid Stimulating Hormone) is secreted by the anterior pituitary gland and stimulates the thyroid to release T3 and T4. The thyroid produces the hormones, adrenal glands secrete cortisol/aldosterone, and parathyroid regulates calcium. Understanding this feedback loop is crucial for managing thyroid disorders and interpreting endocrine physiology.

10. Choose the Correct Statements MCQ:
Statement I: Thyroid hormone regulates basal metabolic rate.
Statement II: Thyroid hormone directly regulates RBC formation.
A) Both statements are correct
B) Both statements are incorrect
C) Only Statement I is correct
D) Only Statement II is correct

Answer & Explanation: Option C is correct. Thyroid hormones increase basal metabolic rate by stimulating energy production and oxygen consumption. They do not directly control RBC formation, which is mainly regulated by erythropoietin from the kidneys. Differentiating these functions is critical in endocrine physiology, disease diagnosis, and understanding hormone-specific systemic effects on metabolism, growth, and homeostasis.

Topic: Endocrine System; Subtopic: Hormones and Target Organs

Keyword Definitions:

• CCK (Cholecystokinin): A digestive hormone secreted by the small intestine to stimulate the release of digestive enzymes from the pancreas and bile from the gallbladder.

• GIP (Gastric Inhibitory Peptide): Hormone released by the small intestine that inhibits gastric motility and stimulates insulin secretion.

• ANF (Atrial Natriuretic Factor): Hormone produced by the atria of the heart to regulate blood pressure by promoting sodium excretion in kidneys.

• ADH (Antidiuretic Hormone): Hormone secreted by the posterior pituitary that regulates water balance by acting on the kidneys.

• Pancreas: Endocrine and exocrine gland producing insulin, glucagon, and digestive enzymes.

• Kidney: Organ responsible for filtering blood, producing urine, and maintaining water and electrolyte balance.

• Heart: Muscular organ that pumps blood and produces hormones like ANF for regulating blood pressure.

• Gastric Gland: Gastric secretory glands in the stomach producing enzymes and acids for digestion.

• Hormone: Chemical messenger secreted by endocrine glands regulating physiological processes.

• Target Organ: Specific organ or tissue on which a hormone exerts its effect.

• Endocrine System: System of glands secreting hormones directly into the bloodstream to regulate body functions.

Lead Question - 2023

Match List I with List II.
List I | List II
A. CCK | I. Kidney
B. GIP | II. Heart
C. ANF | III. Gastric gland
D. ADH | IV. Pancreas

Choose the correct answer from the options given below:
(1) A-II, B-IV, C-I, D-III
(2) A-IV, B-II, C-III, D-I
(3) A-IV, B-III, C-II, D-I
(4) A-III, B-II, C-IV, D-I

Answer & Explanation: (4) A-III, B-II, C-IV, D-I.
CCK (Cholecystokinin) is secreted by the small intestine and acts on the gastric glands to stimulate enzyme secretion. GIP (Gastric Inhibitory Peptide) acts on the heart to modulate cardiac functions indirectly. ANF (Atrial Natriuretic Factor) targets the kidney to increase sodium excretion and lower blood pressure. ADH (Antidiuretic Hormone) also targets the kidney to retain water. Understanding these hormone-target relationships is critical for comprehending physiological regulation of digestion, blood pressure, and water balance. The structural specificity of each hormone ensures precise action on its corresponding target organ.

1. Which hormone primarily regulates water balance in the body?

(1) ANF
(2) ADH
(3) GIP
(4) CCK

ADH (Antidiuretic Hormone) regulates water balance by acting on the kidneys to retain water, reducing urine output. ANF promotes sodium excretion, CCK stimulates digestive enzyme release, and GIP influences insulin secretion. ADH’s role is critical in maintaining osmotic pressure and preventing dehydration, demonstrating hormonal control of homeostasis.

2. Which hormone stimulates pancreatic enzyme secretion?

(1) GIP
(2) ADH
(3) CCK
(4) ANF

CCK (Cholecystokinin) stimulates the pancreas to release digestive enzymes and the gallbladder to secrete bile. This process is essential for protein and fat digestion in the small intestine. GIP regulates insulin, ADH affects water retention, and ANF modulates blood pressure, highlighting specific organ-targeted hormonal action.

3. ANF is secreted by which organ?

(1) Kidney
(2) Heart
(3) Pancreas
(4) Stomach

ANF (Atrial Natriuretic Factor) is secreted by the atria of the heart. It lowers blood pressure by promoting sodium excretion in the kidneys and reducing blood volume. This hormone is part of the cardiovascular-endocrine interaction to maintain homeostasis, in contrast to digestive or water balance hormones like CCK or ADH.

4. Assertion-Reason Type:

Assertion (A): GIP regulates insulin secretion.
Reason (R): GIP is released from the small intestine in response to glucose and fatty acids in the duodenum.
(1) Both A and R are true and R explains A
(2) Both A and R are true but R does not explain A
(3) A is true but R is false
(4) A is false but R is true

Both A and R are true and R explains A. GIP is secreted by the duodenal mucosa when nutrients enter, particularly glucose and lipids. It stimulates insulin release from pancreatic beta cells, linking nutrient detection to metabolic response. This incretin effect is vital for controlling postprandial blood glucose.

5. Fill in the blanks:

______ stimulates bile and pancreatic enzyme secretion, whereas ______ increases water reabsorption in kidneys.
(1) CCK, ADH
(2) GIP, ANF
(3) ANF, ADH
(4) ADH, CCK

CCK stimulates bile release from the gallbladder and pancreatic enzyme secretion for digestion. ADH acts on the kidney to increase water reabsorption, reducing urine output. This demonstrates hormone-specific targeting and functional specialization within the endocrine system.

6. Which hormone targets the gastric gland to regulate digestion?

(1) ADH
(2) ANF
(3) CCK
(4) GIP

CCK indirectly affects gastric glands by stimulating enzyme release for digestion. While GIP inhibits gastric motility, ADH regulates water, and ANF regulates sodium excretion. CCK coordinates digestive secretions in response to food in the duodenum, facilitating nutrient breakdown efficiently.

7. Which hormone is directly involved in lowering blood pressure?

(1) ADH
(2) ANF
(3) CCK
(4) GIP

ANF lowers blood pressure by promoting sodium and water excretion via the kidneys, reducing blood volume. ADH increases water retention, potentially raising blood pressure. CCK and GIP mainly influence digestion and insulin regulation, highlighting the cardiovascular-specific role of ANF.

8. Matching Type:

Match the hormone with its primary target:
List I | List II
A. ADH | I. Pancreas
B. ANF | II. Kidney
C. CCK | III. Gastric gland
D. GIP | IV. Heart

(1) A-II, B-IV, C-III, D-I
(2) A-II, B-IV, C-I, D-III
(3) A-I, B-II, C-III, D-IV
(4) A-IV, B-II, C-III, D-I

Answer: (1) A-II, B-IV, C-III, D-I. ADH acts on the kidney to regulate water reabsorption. ANF targets the heart to modulate blood pressure. CCK stimulates gastric glands and pancreas for digestion. GIP affects insulin secretion via the pancreas. This matching illustrates precise hormone-target specificity in human physiology.

9. Choose the correct statements:

Statement I: ADH increases water retention in kidneys.
Statement II: ANF promotes sodium excretion and lowers blood pressure.
(1) Only Statement I is correct
(2) Only Statement II is correct
(3) Both Statements I and II are correct
(4) Both Statements I and II are false

Both statements are correct. ADH increases water reabsorption in renal collecting ducts, conserving body water. ANF promotes natriuresis (sodium excretion) and decreases blood volume, thereby reducing blood pressure. These complementary hormonal mechanisms maintain fluid balance and cardiovascular homeostasis.

10. Single Correct Answer:

Which hormone inhibits gastric motility while stimulating insulin secretion?
(1) CCK
(2) GIP
(3) ANF
(4) ADH

GIP (Gastric Inhibitory Peptide) inhibits gastric motility and stimulates insulin secretion after food intake. This incretin effect coordinates digestion with glucose metabolism. CCK stimulates enzyme secretion, ANF affects sodium excretion, and ADH regulates water retention. GIP thus integrates nutrient sensing with endocrine response.

11. Single Correct Answer:

Which hormone stimulates enzyme secretion from pancreas and bile release from gallbladder?
(1) ADH
(2) ANF
(3) CCK
(4) GIP

CCK stimulates pancreatic enzyme secretion and gallbladder contraction to release bile, facilitating fat and protein digestion. ADH and ANF regulate water and sodium balance, respectively, while GIP primarily influences insulin secretion. CCK ensures efficient chemical digestion through coordinated secretory responses.

Topic: Reproductive System; Subtopic: Endometrium and Implantation

Lead Question - 2023

Given below are statements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Endometrium is necessary for implantation of blastocyst.
Reason R: In the absence of fertilization, the corpus luteum degenerates that causes disintegration of endometrium.
In the light of the above statements, choose the correct answer from the options given below:
(1) A is true but R is false
(2) A is false but R is true
(3) Both A and R are true and R is the correct explanation of A.
(4) Both A and R are true but R is NOT the correct explanation of A

Answer: (3) Both A and R are true and R is the correct explanation of A. The endometrium is the inner lining of the uterus and provides a suitable environment for implantation and nutrition of the blastocyst. If fertilization does not occur, the corpus luteum degenerates, leading to a drop in progesterone levels. This hormone withdrawal triggers endometrial shedding and menstruation. Therefore, the presence of a functional endometrium maintained by progesterone is essential for successful implantation of the blastocyst.

Keyword Definitions:

• Endometrium: Inner mucosal lining of the uterus essential for implantation and support of early pregnancy.

• Blastocyst: Early stage of embryo, consisting of a hollow ball of cells ready for implantation.

• Corpus Luteum: Temporary endocrine structure in ovary producing progesterone after ovulation.

• Progesterone: Hormone responsible for maintaining endometrium for implantation.

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

• Implantation: Attachment of blastocyst to endometrium for further development.

• Menstruation: Shedding of endometrium in absence of fertilization.

1. Single Correct Answer:

Which hormone maintains the endometrium during early pregnancy?
(1) Estrogen
(2) Progesterone
(3) LH
(4) FSH

Answer: (2) Progesterone. Progesterone produced by corpus luteum stabilizes and maintains the endometrium, making it suitable for implantation and support of early embryonic development.

2. Single Correct Answer:

The degeneracy of corpus luteum leads to:
(1) Ovulation
(2) Menstruation
(3) Fertilization
(4) Implantation

Answer: (2) Menstruation. Degeneration of corpus luteum causes progesterone levels to fall, leading to disintegration and shedding of the endometrium, resulting in menstruation.

3. Single Correct Answer:

Which structure directly interacts with endometrium during implantation?
(1) Ovary
(2) Blastocyst
(3) Corpus luteum
(4) Fallopian tube

Answer: (2) Blastocyst. The blastocyst adheres to the endometrial lining and initiates implantation, supported by hormonal signals primarily from progesterone.

4. Single Correct Answer:

Which event triggers endometrial shedding in absence of fertilization?
(1) Ovulation
(2) Corpus luteum degeneration
(3) Fertilization
(4) Zygote formation

Answer: (2) Corpus luteum degeneration. The corpus luteum produces progesterone, and its degeneration leads to hormone drop causing endometrial breakdown and menstruation.

5. Single Correct Answer:

Which phase of menstrual cycle coincides with endometrium being receptive?
(1) Menstrual
(2) Follicular
(3) Luteal
(4) Ovulatory

Answer: (3) Luteal. The luteal phase follows ovulation, characterized by high progesterone from corpus luteum, preparing endometrium for potential implantation.

6. Single Correct Answer:

Which hormone’s withdrawal causes menstruation?
(1) Estrogen
(2) Progesterone
(3) LH
(4) FSH

Answer: (2) Progesterone. Progesterone withdrawal after corpus luteum degeneration leads to disintegration of the endometrium and onset of menstruation.

7. Assertion-Reason:

Assertion A: Endometrium provides nutrients for blastocyst.
Reason R: Progesterone from corpus luteum maintains endometrial thickness.
(1) A true, R false
(2) A false, R true
(3) Both true, R explains A
(4) Both true, R does not explain A

Answer: (3) Both true, R explains A. Progesterone maintains a thick, vascular endometrium which supplies nutrients and a suitable environment for implantation of blastocyst.

8. Matching Type:

Match hormones with their function:
List I | List II
A. Progesterone | I. Maintains endometrium
B. Estrogen | II. Follicle maturation
C. LH | III. Ovulation
Options:
(1) A-I, B-II, C-III
(2) A-II, B-I, C-III
(3) A-I, B-III, C-II
(4) A-III, B-II, C-I

Answer: (1) A-I, B-II, C-III. Progesterone maintains endometrium, estrogen supports follicle growth, LH triggers ovulation.

9. Fill in the Blanks:

The ________ maintains the endometrium for implantation after ovulation.
Options: (1) Ovary (2) Corpus luteum (3) Fallopian tube (4) Pituitary

Answer: (2) Corpus luteum. The corpus luteum secretes progesterone to stabilize the endometrium, making it receptive for blastocyst implantation.

10. Choose Correct Statements:

Statement I: Progesterone is essential for endometrial maintenance.
Statement II: Endometrium disintegrates if fertilization does not occur.
Options:
(1) Both true
(2) I true, II false
(3) I false, II true
(4) Both false

Answer: (1) Both true. Progesterone sustains the endometrium, and in absence of fertilization, corpus luteum degenerates causing hormone drop, leading to endometrial shedding.

Topic: Male and Female Reproductive Systems; Subtopic: Reproductive Ducts and Birth Canal

Keyword Definitions:

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

• Seminal vesicle: A gland that secretes a fructose-rich fluid forming a part of the semen.

• Ejaculatory duct: Formed by the union of vas deferens and the duct of seminal vesicle; opens into the urethra.

• Urethra: A common duct for both urinary and reproductive systems in males, carrying urine and semen.

• Cervix: The lower narrow part of the uterus connecting it to the vagina; forms the cervical canal.

• Cervical canal: Passage through cervix that connects uterine cavity to the vagina, aiding sperm movement and childbirth.

• Birth canal: Passage formed by the cervix and vagina through which the baby is delivered during parturition.

• Seminal fluid: A nutrient-rich liquid produced by seminal vesicles, prostate, and bulbourethral glands, nourishing sperm.

• Prostate gland: Secretes alkaline fluid that enhances sperm motility and neutralizes vaginal acidity.

• Vagina: Muscular tubular part of female reproductive tract that serves as copulatory organ and birth canal.

• Parturition: Process of childbirth where rhythmic contractions expel the baby through the birth canal.

Lead Question - 2023:

Given below are two statements:
Statement I: Vas deferens receives a duct from seminal vesicle and opens into urethra as the ejaculatory duct.
Statement II: The cavity of the cervix is called cervical canal which along with vagina forms birth canal.
In the light of the above statements, choose the correct answer from the options given below:
(1) Statement I is correct but Statement II is false
(2) Statement I incorrect but Statement II is true
(3) Both Statement I and Statement II are true
(4) Both Statement I and Statement II are false

Answer & Explanation: (3) Both Statement I and Statement II are true. The vas deferens receives a duct from the seminal vesicle forming the ejaculatory duct that opens into the urethra for semen discharge. The cervix contains the cervical canal connecting the uterus to the vagina, which together form the birth canal aiding childbirth. Both structures have essential reproductive functions coordinating male and female physiology.

1. The ejaculatory duct is formed by the union of:
(1) Vas deferens and urethra
(2) Vas deferens and seminal vesicle duct
(3) Seminal vesicle and prostate gland
(4) Epididymis and vas deferens
Explanation: The ejaculatory duct forms where the vas deferens joins the duct of the seminal vesicle. Correct answer is (2). This duct passes through the prostate to open into the urethra, carrying semen during ejaculation. It ensures sperm mixing with seminal secretions for nutrition and motility enhancement before release.

2. The function of seminal vesicle secretion is to:
(1) Provide nourishment to sperm
(2) Promote fertilization
(3) Activate ovum
(4) Facilitate urine passage
Explanation: Seminal vesicle secretions contain fructose, citric acid, and prostaglandins which nourish sperm and enhance motility. Correct answer is (1). This secretion forms about 60% of semen volume, maintaining sperm viability during transit in the female reproductive tract for successful fertilization.

3. The common duct for urine and semen in males is called:
(1) Vas deferens
(2) Ejaculatory duct
(3) Urethra
(4) Seminiferous tubule
Explanation: Urethra serves as the common passage for both semen and urine in males. Correct answer is (3). It extends through the penis, opening at the tip. During ejaculation, a sphincter closes the bladder opening, preventing urine mixing with semen and ensuring reproductive efficiency.

4. The cervix is located between:
(1) Ovary and oviduct
(2) Uterus and vagina
(3) Oviduct and uterus
(4) Vulva and vagina
Explanation: The cervix is the lower narrow part of the uterus connecting it with the vagina. Correct answer is (2). It forms the cervical canal which allows sperm entry and menstrual discharge. During labor, it dilates to facilitate childbirth through the birth canal.

5. The birth canal in females is formed by:
(1) Cervix and vagina
(2) Uterus and oviduct
(3) Vagina and vulva
(4) Cervix and uterus
Explanation: The cervix and vagina together constitute the birth canal through which the baby is delivered during parturition. Correct answer is (1). The cervix acts as a gateway to the uterus, while the vagina serves as the passage for delivery, menstrual flow, and copulation.

6. Semen differs from sperm because:
(1) Sperm is non-living
(2) Semen is a mixture of sperm and glandular fluids
(3) Semen contains only hormones
(4) Sperm is secreted by glands
Explanation: Semen is a composite fluid containing spermatozoa and secretions from accessory glands like seminal vesicles, prostate, and bulbourethral glands. Correct answer is (2). These fluids provide nutrients, lubrication, and medium for sperm transport, essential for successful fertilization and reproduction.

Assertion-Reason Question
7. Assertion (A): Ejaculatory duct connects vas deferens to urethra.
Reason (R): It allows mixing of sperm with seminal vesicle fluid before ejaculation.
(1) Both A and R are true, and R explains A
(2) Both A and R are true, but R does not explain A
(3) A true, R false
(4) A false, R true
Explanation: Both statements are true and R correctly explains A. Ejaculatory ducts ensure sperm mixes with seminal secretions before release through urethra, forming semen. Correct answer is (1). This process ensures sperm nourishment, fluidity, and optimum pH for fertilization success in males.

Matching Type Question
8. Match the following structures with their functions:
A. Vas deferens – i. Transports sperm to ejaculatory duct
B. Seminal vesicle – ii. Secretes fructose-rich fluid
C. Cervical canal – iii. Connects uterus and vagina
D. Urethra – iv. Common passage for semen and urine
(1) A-i, B-ii, C-iii, D-iv
(2) A-ii, B-i, C-iii, D-iv
(3) A-i, B-iii, C-ii, D-iv
(4) A-iv, B-ii, C-i, D-iii
Explanation: Vas deferens carries sperm to the ejaculatory duct; seminal vesicle secretes nutritive fluid; cervical canal joins uterus and vagina; urethra serves as the common outlet for urine and semen. Correct answer is (1). These functions coordinate reproductive efficiency in both sexes.

Fill in the Blanks Question
9. The ejaculatory duct opens into the _______ in males.
(1) Ureter
(2) Urethra
(3) Urinary bladder
(4) Epididymis
Explanation: Ejaculatory ducts open into the urethra, which serves as the passage for semen expulsion. Correct answer is (2). The urethra ensures coordinated discharge of semen during ejaculation while preventing mixing of urine and reproductive fluids through sphincteric control.

Choose the Correct Statements Question
10. Statement I: Seminal vesicle fluid contains fructose and prostaglandins.
Statement II: Ejaculatory duct opens into urinary bladder.
(1) Both I and II true
(2) Only I true
(3) Only II true
(4) Both false
Explanation: Seminal vesicle fluid is rich in fructose and prostaglandins that energize and stimulate sperm motility. The ejaculatory duct opens into urethra, not bladder. Correct answer is (2). These secretions help ensure sperm survival and mobility, crucial for fertilization process in males.

Topic: Female Reproductive Cycle; Subtopic: Menstrual and Oestrus Cycles

Keyword Definitions:

• Menstrual Cycle: A series of cyclic events in females involving ovulation and preparation of the uterus for pregnancy, occurring roughly every 28 days.

• Oestrus Cycle: Reproductive cycle in non-primate mammals characterized by recurring periods of sexual receptivity called oestrus or “heat.”

• Menarche: The first menstrual bleeding marking the onset of puberty in human females.

• Menopause: Permanent cessation of menstruation indicating the end of reproductive ability in females.

• Pregnancy: Condition of carrying a developing embryo or fetus within the female body after fertilization.

• Ovulation: Release of a mature ovum from the ovary during the menstrual cycle, typically mid-cycle.

• Corpus Luteum: Hormone-secreting structure formed after ovulation, producing progesterone for uterine maintenance.

• Estrogen: Hormone responsible for developing female secondary sexual characteristics and regulating reproductive cycles.

• Progesterone: Hormone that prepares the endometrium for possible pregnancy after ovulation.

• Uterine Cycle: Periodic structural and functional changes in the endometrium coordinated with ovarian hormones.

• Puberty: Developmental phase when the reproductive system matures, and secondary sexual characteristics appear.

Lead Question - 2023:

Which of the following statements are correct regarding female reproductive cycle?
(A) In non-primate mammals cyclical changes during reproduction are called oestrus cycle.
(B) First menstrual cycle begins at puberty and is called menopause.
(C) Lack of menstruation may be indicative of pregnancy.
(D) Cyclic menstruation extends between menarche and menopause.
Choose the most appropriate answer from the options given below:
(1) A, B and C only
(2) A, C and D only
(3) A and D only
(4) A and B only

Answer & Explanation: (2) A, C and D only. The oestrus cycle occurs in non-primate mammals, while primates show menstrual cycles. Menarche marks the onset of menstruation at puberty, not menopause. Pregnancy halts menstruation due to hormonal maintenance of the endometrium. The menstrual cycle continues cyclically between menarche and menopause, regulated by estrogen and progesterone levels controlling uterine and ovarian changes effectively.

1. Menarche refers to:
(1) End of menstruation
(2) Beginning of menstruation
(3) Period of ovulation
(4) Phase of pregnancy
Explanation: Menarche marks the beginning of the menstrual cycle in females during puberty. It signifies the attainment of sexual maturity. Correct answer is (2). This event indicates hormonal activation of ovaries and uterus for potential reproduction. It continues cyclically until menopause, defining a woman’s reproductive age span controlled by gonadotropins and ovarian hormones.

2. Menopause occurs due to:
(1) High estrogen levels
(2) Cessation of ovarian activity
(3) High progesterone levels
(4) Ovulation every month
Explanation: Menopause occurs when ovaries stop releasing ova and producing estrogen and progesterone. It marks the end of reproductive capacity. Correct answer is (2). The absence of hormones leads to cessation of uterine and ovarian cycles, resulting in end of menstruation, typically around 45–50 years of age in females.

3. The hormone mainly responsible for ovulation is:
(1) LH
(2) FSH
(3) Estrogen
(4) Progesterone
Explanation: Luteinizing hormone (LH) surge triggers ovulation, releasing a mature ovum from the Graafian follicle. Correct answer is (1). LH also initiates corpus luteum formation, producing progesterone to prepare the uterus for implantation if fertilization occurs, maintaining reproductive cycle regulation in coordination with other pituitary hormones.

4. Which phase of menstrual cycle shows maximum estrogen secretion?
(1) Follicular phase
(2) Luteal phase
(3) Menstrual phase
(4) Secretory phase
Explanation: Estrogen levels peak during the follicular phase, stimulating endometrial thickening and follicular growth. Correct answer is (1). The high estrogen level triggers the LH surge leading to ovulation. It helps prepare the endometrium for potential implantation, coordinating with FSH for follicular development.

5. Absence of menstruation in sexually mature female is termed:
(1) Menorrhagia
(2) Amenorrhea
(3) Dysmenorrhea
(4) Polymenorrhea
Explanation: Amenorrhea is the absence of menstrual bleeding, commonly caused by pregnancy, hormonal imbalance, or stress. Correct answer is (2). Physiological amenorrhea occurs during pregnancy and lactation, while pathological cases arise due to hormonal or anatomical disorders affecting the hypothalamic-pituitary-ovarian axis regulation.

6. Which hormone maintains endometrium during pregnancy?
(1) LH
(2) Progesterone
(3) Estrogen
(4) Oxytocin
Explanation: Progesterone maintains endometrial lining, preventing menstruation during pregnancy. Correct answer is (2). It is secreted by corpus luteum initially and later by placenta. It supports implantation and prevents uterine contractions, crucial for sustaining the developing embryo until parturition.

Assertion-Reason Question
7. Assertion (A): Menstrual cycle prepares uterus for possible pregnancy.
Reason (R): Corpus luteum secretes progesterone to maintain endometrial lining.
(1) Both A and R true, R explains A
(2) Both A and R true, R doesn’t explain A
(3) A true, R false
(4) A false, R true
Explanation: Menstrual cycle prepares the endometrium to support implantation, achieved by progesterone secreted from corpus luteum. Both statements are true, and R correctly explains A. Correct answer is (1). This hormonal synchronization ensures reproductive readiness and cyclical regeneration of uterine lining in females.

Matching Type Question
8. Match the phases of menstrual cycle with their major events:
A. Follicular Phase – i. LH surge and ovulation
B. Ovulatory Phase – ii. Estrogen secretion
C. Luteal Phase – iii. Progesterone secretion
(1) A-ii, B-i, C-iii
(2) A-i, B-ii, C-iii
(3) A-iii, B-ii, C-i
(4) A-ii, B-iii, C-i
Explanation: Follicular phase involves estrogen secretion and follicle development, ovulatory phase shows LH surge, and luteal phase secretes progesterone for uterine maintenance. Correct answer is (1). These phases ensure coordination of ovarian and uterine cycles essential for fertility and reproductive health.

Fill in the Blanks Question
9. The first menstrual bleeding at puberty is called _______.
(1) Menopause
(2) Menarche
(3) Ovulation
(4) Fertilization
Explanation: Menarche marks the beginning of menstrual cycles at puberty, signaling functional maturity of reproductive organs. Correct answer is (2). It results from hormonal activation of ovaries and uterus under pituitary control, initiating fertility period in females until menopause.

Choose the Correct Statements Question
10. Statement I: Menarche and menopause define the reproductive phase in women.
Statement II: Oestrus cycle occurs in primates.
(1) Only Statement I correct
(2) Only Statement II correct
(3) Both I and II correct
(4) Both I and II incorrect
Explanation: Menarche and menopause mark the beginning and end of female reproductive age, respectively. Oestrus cycle occurs in non-primates, not in primates. Correct answer is (1). These terms collectively describe female reproductive physiology and hormonal control of fertility period.

Chapter: Human Reproduction; Topic: Male Reproductive System; Subtopic: Spermatogenesis

Keyword Definitions:
• Secondary Spermatocytes: Haploid cells formed from primary spermatocytes during meiosis I; they divide to form spermatids.
• Spermatozoa: Mature male gametes capable of fertilizing an ovum.
• Spermatogenesis: Process of formation of sperm from spermatogonial stem cells in testes.
• Primary Spermatocytes: Diploid cells that undergo meiosis I to form secondary spermatocytes.
• Meiosis: Special type of cell division producing haploid gametes from diploid cells.

Lead Question - 2022 (Ganganagar)

How many secondary spermatocytes are required to form 400 million spermatozoa?

1. 50 million
2. 100 million
3. 200 million
4. 400 million

Explanation: The correct answer is option 2 (100 million). Each secondary spermatocyte undergoes meiosis II to produce 2 spermatids, which further differentiate into 2 spermatozoa. Therefore, 100 million secondary spermatocytes will produce 200 million spermatids, and after differentiation, they result in 400 million spermatozoa. This illustrates the efficiency of meiosis and the amplification of gametes in male reproductive system.

1. Each primary spermatocyte produces how many spermatozoa after complete spermatogenesis?
1. 2
2. 4
3. 16
4. 8

Explanation: The correct answer is 4. Each primary spermatocyte undergoes meiosis I to form 2 secondary spermatocytes. Each secondary spermatocyte undergoes meiosis II to form 2 spermatids, totaling 4 spermatids, which then differentiate into 4 spermatozoa.

2. Which hormone stimulates spermatogenesis in testes?
1. LH
2. FSH
3. Testosterone
4. Prolactin

Explanation: The correct answer is FSH. Follicle-stimulating hormone from the anterior pituitary stimulates Sertoli cells, which support spermatogenesis. Testosterone supports differentiation of spermatids into spermatozoa.

3. The process of sperm maturation occurs in:
1. Seminiferous tubules
2. Epididymis
3. Vas deferens
4. Prostate gland

Explanation: The correct answer is epididymis. Spermatids released from seminiferous tubules enter epididymis where they undergo functional and structural maturation, acquiring motility and the ability to fertilize an ovum.

4. Which cells provide nourishment to developing spermatozoa?
1. Leydig cells
2. Sertoli cells
3. Spermatogonia
4. Myoid cells

Explanation: The correct answer is Sertoli cells. These cells line the seminiferous tubules and provide structural support, nutrients, and hormonal signals to developing spermatogenic cells, facilitating proper spermatogenesis.

5. At which stage are the spermatids haploid?
1. Primary spermatocyte
2. Secondary spermatocyte
3. Spermatogonia
4. Mature spermatozoa

Explanation: The correct answer is secondary spermatocyte. Secondary spermatocytes are haploid (n) as a result of meiosis I. They divide by meiosis II to produce spermatids, which are also haploid, eventually differentiating into spermatozoa.

6. Where does meiosis occur in male reproductive system?
1. Epididymis
2. Seminiferous tubules
3. Vas deferens
4. Prostate gland

Explanation: The correct answer is seminiferous tubules. Primary spermatocytes in seminiferous tubules undergo meiosis I to form secondary spermatocytes, and meiosis II to form spermatids. This occurs within the germinal epithelium of tubules.

7. Assertion-Reason Question:
Assertion (A): Secondary spermatocytes are haploid cells.
Reason (R): They are formed after meiosis I of primary spermatocytes.

1. Both A and R are true, and R is correct explanation for A
2. Both A and R are true, but R is not the correct explanation for A
3. A true, R false
4. A false, R true

Explanation: The correct answer is option 1. Secondary spermatocytes are haploid because primary spermatocytes undergo meiosis I, reducing chromosome number by half. Therefore, both assertion and reason are correct, and the reason explains the assertion.

8. Matching Type:
Match the stages with chromosome number:
(a) Primary spermatocyte - (i) 2n
(b) Secondary spermatocyte - (ii) n
(c) Spermatid - (iii) n

1. (a)-(i), (b)-(ii), (c)-(iii)
2. (a)-(ii), (b)-(i), (c)-(iii)
3. (a)-(i), (b)-(iii), (c)-(ii)
4. (a)-(iii), (b)-(ii), (c)-(i)

Explanation: The correct answer is option 1. Primary spermatocytes are diploid (2n), secondary spermatocytes are haploid (n), and spermatids are also haploid (n). This progression ensures proper halving of chromosome number for sexual reproduction.

9. Fill in the Blanks:
Spermatogenesis occurs in the ________ of testes.

1. Epididymis
2. Seminiferous tubules
3. Vas deferens
4. Rete testis

Explanation: The correct answer is seminiferous tubules. Spermatogonia in the germinal epithelium of seminiferous tubules divide and differentiate through meiosis to produce spermatocytes, spermatids, and eventually mature spermatozoa.

10. Choose the Correct Statements:
Statement I: Each secondary spermatocyte produces two spermatids.
Statement II: Spermatids differentiate into spermatozoa in epididymis.

1. Both I and II are correct
2. Both I and II are incorrect
3. Only I correct
4. Only II correct

Explanation: The correct answer is option 1. Each secondary spermatocyte undergoes meiosis II to form two spermatids. These spermatids undergo structural and functional maturation in epididymis to become motile spermatozoa, completing the process of spermatogenesis.

Chapter: Human Reproduction; Topic: Female Reproductive System; Subtopic: Mammary Gland Structure and Function

Keyword Definitions:

• Mammary Glands: Specialized exocrine glands that produce milk to nourish newborns.

• Alveoli: Milk-secreting sacs lined with cuboidal epithelial cells.

• Mammary Tubules: Ducts that collect milk from alveoli.

• Mammary Ducts: Channels that transport milk to ampullae.

• Mammary Ampulla: Dilated part where milk is temporarily stored.

• Lactiferous Duct: Final duct through which milk exits via the nipple.

Lead Question - 2022 (Ganganagar)

Arrange the components of mammary gland (from proximal to distal):

(a) Mammary duct

(b) Lactiferous duct

(c) Alveoli

(d) Mammary ampulla

(e) Mammary tubules

Choose the most appropriate answer from the options given below:

1. (c) → (a) → (d) → (e) → (b)

2. (b) → (c) → (e) → (d) → (a)

3. (c) → (e) → (a) → (d) → (b)

4. (e) → (c) → (d) → (b) → (a)

Explanation:

The correct order is (c) → (e) → (a) → (d) → (b). Milk is secreted by alveoli, carried through mammary tubules into mammary ducts, temporarily stored in mammary ampulla, and finally released through lactiferous ducts. This sequence ensures smooth milk passage from secretory units to the nipple during lactation. (Answer: 3)

Guessed Question 1:

Which of the following cells line the alveoli of mammary glands?

1. Cuboidal epithelial cells

2. Squamous epithelial cells

3. Ciliated epithelial cells

4. Columnar epithelial cells

Explanation:

The alveoli of mammary glands are lined by cuboidal epithelial cells that secrete milk and are surrounded by myoepithelial cells aiding in milk ejection. These cuboidal cells respond to prolactin, promoting milk synthesis after childbirth, while oxytocin stimulates contraction for milk flow. (Answer: 1)

Guessed Question 2:

Which hormone stimulates milk ejection from mammary glands?

1. Oxytocin

2. Estrogen

3. Prolactin

4. Progesterone

Explanation:

Oxytocin from the posterior pituitary triggers contraction of myoepithelial cells around alveoli, forcing milk into ducts and ampullae, leading to milk ejection or “let-down reflex.” Prolactin aids in milk synthesis, while oxytocin aids in milk release. (Answer: 1)

Guessed Question 3:

Milk secretion in the mammary glands is primarily regulated by which hormone?

1. Oxytocin

2. Prolactin

3. LH

4. FSH

Explanation:

Prolactin, secreted by the anterior pituitary gland, stimulates alveolar epithelial cells to produce milk. Its secretion increases after childbirth, ensuring continuous milk synthesis, while oxytocin controls milk ejection. LH and FSH are unrelated to lactation. (Answer: 2)

Guessed Question 4:

During pregnancy, mammary gland development is promoted mainly by:

1. Estrogen and Progesterone

2. LH and FSH

3. Testosterone

4. Prolactin only

Explanation:

Estrogen promotes ductal growth, while progesterone stimulates alveolar and lobular development of the mammary gland. Together they prepare the breast for lactation. After delivery, prolactin maintains milk production and oxytocin facilitates milk release. (Answer: 1)

Guessed Question 5:

Which structure of the mammary gland stores milk before suckling?

1. Mammary duct

2. Mammary ampulla

3. Lactiferous duct

4. Alveoli

Explanation:

The mammary ampulla acts as a temporary storage chamber for milk before it passes through the lactiferous duct during suckling. This ensures milk is readily available for the infant when required. (Answer: 2)

Guessed Question 6:

Which cells assist in the expulsion of milk from alveoli during lactation?

1. Myoepithelial cells

2. Cuboidal cells

3. Ciliated cells

4. Basal cells

Explanation:

Myoepithelial cells surround the alveoli and ducts of mammary glands. Under oxytocin influence, these cells contract and squeeze milk from alveoli into ducts, ensuring milk reaches the nipple efficiently during lactation. (Answer: 1)

Guessed Question 7 (Assertion-Reason):

Assertion (A): Oxytocin causes contraction of myoepithelial cells.

Reason (R): Myoepithelial cells are present in seminiferous tubules of testes.

1. Both A and R are true, and R is the correct explanation of A.

2. Both A and R are true, but R is not the correct explanation of A.

3. A is true, but R is false.

4. A is false, but R is true.

Explanation:

Assertion is true as oxytocin stimulates contraction of myoepithelial cells for milk ejection. Reason is false because myoepithelial cells are found in mammary glands, not seminiferous tubules. Thus, A is true but R is false. (Answer: 3)

Guessed Question 8 (Matching Type):

Match the following hormones with their functions in lactation:

(a) Prolactin

(b) Oxytocin

(c) Estrogen

(d) Progesterone

List-II:

(i) Milk synthesis

(ii) Milk ejection

(iii) Duct growth

(iv) Alveolar growth

1. (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv)

2. (a)-(ii), (b)-(i), (c)-(iii), (d)-(iv)

3. (a)-(iii), (b)-(ii), (c)-(iv), (d)-(i)

4. (a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)

Explanation:

Prolactin stimulates milk synthesis, oxytocin promotes milk ejection, estrogen supports ductal growth, and progesterone aids alveolar development. Hence the correct matching is (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv). (Answer: 1)

Guessed Question 9 (Fill in the Blanks):

During lactation, the hormone ________ maintains milk production in the mammary glands.

1. Oxytocin

2. Prolactin

3. Estrogen

4. LH

Explanation:

Prolactin is essential for maintaining milk secretion throughout the lactation period. Its levels remain high during breastfeeding, ensuring a continuous milk supply, while oxytocin triggers milk ejection. (Answer: 2)

Guessed Question 10 (Choose the Correct Statements):

Statement I: Oxytocin is secreted from the anterior pituitary gland.

Statement II: Prolactin helps in milk production from mammary glands.

1. Both statements are true.

2. Both statements are false.

3. Statement I is true, Statement II is false.

4. Statement I is false, Statement II is true.

Explanation:

Statement I is false because oxytocin is released from the posterior pituitary gland, not the anterior. Statement II is true as prolactin secreted by the anterior pituitary regulates milk production. Thus, correct option is (4). (Answer: 4)

Topic: Male Reproductive System; Subtopic: Male Accessory Ducts

Keyword Definitions:

• Testis: The primary male reproductive organ that produces sperms and the hormone testosterone.

• Epididymis: A long, coiled tube where sperm matures and is stored temporarily.

• Vasa efferentia: Fine ducts that transport sperms from the rete testis to the epididymis.

• Vas deferens: A muscular tube that carries mature sperms from the epididymis to the ejaculatory duct.

• Ejaculatory duct: The final duct through which sperms mix with seminal fluids before entering the urethra for ejaculation.

Lead Question - 2022 (Abroad)
Arrange the following male sex accessory ducts in the correct sequence for the transport of sperms from the testis:
(a) Epididymis
(b) Ejaculatory duct
(c) Vasa efferentia
(d) Rete testis
(e) Vas deferens
1. (d), (a), (c), (e), (b)
2. (d), (c), (e), (a), (b)
3. (d), (c), (a), (e), (b)
4. (d), (e), (a), (c), (b)

Explanation:
The correct sequence for sperm transport is rete testis → vasa efferentia → epididymis → vas deferens → ejaculatory duct. Sperms produced in seminiferous tubules enter rete testis, then pass through vasa efferentia to reach epididymis for maturation, continue through vas deferens, and finally reach the ejaculatory duct. Thus, option 3 is correct.

1. Which of the following stores the sperm temporarily before ejaculation?
1. Prostate gland
2. Epididymis
3. Urethra
4. Bulbourethral gland

Explanation:
Epididymis serves as a site for sperm maturation and temporary storage. Sperms gain motility and fertilizing ability while passing through it. During ejaculation, sperms are propelled from the epididymis through the vas deferens. Therefore, epididymis acts as the temporary sperm storage organ.

2. Which of the following connects rete testis to the epididymis?
1. Vas deferens
2. Vasa efferentia
3. Ejaculatory duct
4. Urethra

Explanation:
Vasa efferentia are fine ducts that transport immature sperms from rete testis to the epididymis. Here, sperms undergo maturation and storage before being transferred to vas deferens during ejaculation. Hence, the connecting ducts are vasa efferentia.

3. Which gland contributes fructose to the seminal fluid?
1. Prostate gland
2. Seminal vesicle
3. Bulbourethral gland
4. Cowper’s gland

Explanation:
Seminal vesicles secrete a viscous fluid rich in fructose, which provides energy to sperm cells for motility. This secretion also contains prostaglandins and proteins that support fertilization. Therefore, seminal vesicle is the gland responsible for fructose secretion in seminal fluid.

4. What is the function of the ejaculatory duct?
1. Storage of sperm
2. Conduction of sperms and seminal fluid
3. Secretion of testosterone
4. Formation of spermatids

Explanation:
The ejaculatory duct carries sperm from the vas deferens and mixes it with secretions from seminal vesicles to form semen. It acts as a short passageway that opens into the urethra during ejaculation. Hence, its main function is conduction of sperms and seminal fluid.

5. Which among the following is a paired structure in the male reproductive system?
1. Prostate gland
2. Seminal vesicle
3. Urethra
4. Penis

Explanation:
Seminal vesicles are paired glands located posterior to the urinary bladder. Each seminal vesicle contributes fluid to semen, which nourishes and protects sperm. In contrast, the prostate and urethra are single structures. Therefore, the paired structure is seminal vesicle.

6. The testis is located outside the abdominal cavity in the scrotum because:
1. High temperature is needed for spermatogenesis
2. Low temperature is required for spermatogenesis
3. It provides protection against injury
4. It helps in the secretion of testosterone

Explanation:
Spermatogenesis requires a temperature 2–2.5°C lower than the body’s core temperature. The scrotum helps maintain this lower temperature by positioning the testes outside the abdominal cavity. Therefore, the testis is located in the scrotum for optimal sperm production.

7. (Assertion-Reason Type)
Assertion (A): Vas deferens carries sperm from epididymis to ejaculatory duct.
Reason (R): Vas deferens is a muscular tube that conducts sperm through peristaltic contractions.
1. Both A and R are true, and R explains A
2. Both A and R are true, but R does not explain A
3. A is true but R is false
4. A is false but R is true

Explanation:
Vas deferens transports mature sperms from the epididymis to the ejaculatory duct using muscular peristalsis. This ensures efficient propulsion of sperms during ejaculation. Thus, both assertion and reason are true, and the reason correctly explains the assertion.

8. (Matching Type)
Match the following structures with their functions:
A. Epididymis – (i) Conducts sperms to ejaculatory duct
B. Vas deferens – (ii) Storage and maturation of sperms
C. Ejaculatory duct – (iii) Receives sperms and seminal vesicle secretions
1. A-(ii), B-(i), C-(iii)
2. A-(i), B-(ii), C-(iii)
3. A-(iii), B-(ii), C-(i)
4. A-(ii), B-(iii), C-(i)

Explanation:
Epididymis stores and matures sperms (A-ii), vas deferens conducts sperms to the ejaculatory duct (B-i), and the ejaculatory duct receives sperm and seminal vesicle secretions before ejaculation (C-iii). Thus, the correct matching is A-(ii), B-(i), C-(iii).

9. (Fill in the Blanks)
The site of sperm maturation and storage before ejaculation is the ________.
1. Testis
2. Epididymis
3. Vas deferens
4. Ejaculatory duct

Explanation:
Epididymis is a coiled structure on the posterior side of each testis where sperms mature and are stored. They gain motility and fertilization ability here before being transferred through vas deferens. Hence, epididymis is the correct answer.

10. (Choose the Correct Statements)
Statement I: Vas deferens and urethra are continuous ducts.
Statement II: Ejaculatory duct opens into the urethra.
1. Statement I correct, Statement II incorrect
2. Statement I incorrect, Statement II correct
3. Both statements correct
4. Both statements incorrect

Explanation:
Vas deferens joins with the duct of seminal vesicle to form the ejaculatory duct, which then opens into the urethra. Thus, vas deferens and urethra are not continuous ducts, but the ejaculatory duct indeed opens into the urethra. Hence, Statement II is correct.