Human Reproduction — Questions & Answers

Sample questions from Human Reproduction

1. Q1. The enlarged tip of the penis and the loose fold of skin that covers it are respectively called:

   • A.Scrotum and prepuce
   • B.Glans penis and foreskin✓
   • C.Urethral meatus and glans
   • D.Foreskin and glans penis
   Solution

   The penis is the male external genitalia made of special tissue that helps erection; its enlarged end is the glans penis, which is covered by a loose fold of skin called the foreskin (prepuce). Option D reverses the terms.

2. Q2. A woman shows a normal LH surge and follicular growth but her endometrium never thickens during the follicular phase. The most likely defect is in:

   • A.The response of the endometrium to estrogen secreted by the growing follicle✓
   • B.The secretion of oxytocin by the pituitary
   • C.Spermiation in her partner
   • D.The formation of the corpus albicans
   Solution

   During the follicular (proliferative) phase the growing follicle secretes estrogen, under whose influence the endometrium regenerates and proliferates. A normal LH surge and follicular growth rule out a pituitary or ovarian growth fault, so an endometrial failure to respond to estrogen best explains the finding.

3. Q3. Arrange the following developmental events in the correct chronological order of human pregnancy: (i) most major organ systems formed, (ii) heart formed, (iii) eyelids separate and eyelashes formed, (iv) first foetal movements felt.

   • A.(i), (ii), (iii), (iv)
   • B.(ii), (iv), (i), (iii)
   • C.(iv), (ii), (i), (iii)
   • D.(ii), (i), (iv), (iii)✓
   Solution

   The heart is formed after about one month, most major organ systems by the end of 12 weeks, the first foetal movements appear in the fifth month, and by the end of 24 weeks the body is covered with fine hair, the eyelids separate and eyelashes are formed.

4. Q4. Why is testosterone alone, without FSH, generally insufficient to sustain fully normal, quantitatively adequate spermatogenesis?

   • A.Testosterone has no role in the testis at all
   • B.FSH is independently required to support Sertoli cell function, which testosterone alone cannot replace✓
   • C.Testosterone actively destroys sperm
   • D.FSH and testosterone act on identical receptors, making one redundant
   Solution

   Testosterone (via Leydig cells) and FSH (via Sertoli cells) act through distinct pathways that both converge to support spermatogenesis; FSH-driven Sertoli cell support cannot be fully substituted by testosterone alone, so both are normally required for quantitatively normal sperm production.

5. Q5. In the female external genitalia, the tiny finger-like structure that lies at the upper junction of the two labia minora, above the urethral opening, is the:

   • A.Hymen
   • B.Mons pubis
   • C.Clitoris✓
   • D.Labium majus
   Solution

   The clitoris is a tiny finger-like structure located at the upper junction of the two labia minora above the urethral opening. The hymen partially covers the vaginal opening, mons pubis is the fatty cushion, and labia majora are the outer fleshy folds.

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