Human Reproduction

What you'll learn

A patient, step-by-step walk through the male and female reproductive systems, spermatogenesis and oogenesis, the menstrual cycle, fertilisation, and the first days of embryonic development — exactly as the NCERT Class 12 syllabus expects.

This chapter has

Human Reproduction — solved practice questions

8 Class 12 Biology questions with step-by-step solutions. Attempt each, then reveal the answer.

1. Q1easy

   The process of formation of sperms from the male germ cells in the testis is called:

   • ASpermatogenesis
   • BOogenesis
   • CSpermiation
   • DSpermiogenesis
   Show answer & solution

   Correct answer: (A) Spermatogenesis

   Spermatogenesis is the process by which spermatogonia (2n) form haploid sperms in the seminiferous tubules of the testis.

2. Q2easy

   Within the seminiferous tubules, the cells that provide nutrition and support to the developing germ cells are the:

   • ALeydig cells
   • BInterstitial cells
   • CGerm cells
   • DSertoli cells
   Show answer & solution

   Correct answer: (D) Sertoli cells

   Sertoli cells line the seminiferous tubules and nourish the developing germ cells. Leydig (interstitial) cells lie outside the tubules and secrete androgens.

3. Q3medium

   The Leydig cells (interstitial cells) present in the spaces between the seminiferous tubules mainly secrete:

   • AEstrogen
   • BProgesterone
   • CAndrogens (testosterone)
   • DInhibin
   Show answer & solution

   Correct answer: (C) Androgens (testosterone)

   Leydig cells synthesise and secrete testicular hormones called androgens (mainly testosterone), which stimulate spermatogenesis and secondary sexual characters.

4. Q4easy

   The normal gestation (pregnancy) period in humans is approximately:

   • A6 months
   • B9 months
   • C12 months
   • D3 months
   Show answer & solution

   Correct answer: (B) 9 months

   Human gestation lasts about 9 months (roughly 280 days) from the last menstrual period to birth.

5. Q5medium

   The transformation of spermatids into mature, motile spermatozoa is called:

   • ASpermatogenesis
   • BSpermiation
   • CSpermatocytosis
   • DSpermiogenesis
   Show answer & solution

   Correct answer: (D) Spermiogenesis

   Spermiogenesis is the differentiation of non-motile spermatids into streamlined, motile spermatozoa; spermiation is their subsequent release into the tubule lumen.

6. Q6medium

   The rapid surge of which hormone at about the 14th day of the menstrual cycle induces ovulation?

   • ALuteinizing hormone (LH)
   • BFSH
   • CProgesterone
   • DEstrogen
   Show answer & solution

   Correct answer: (A) Luteinizing hormone (LH)

   The mid-cycle LH surge (luteinizing hormone) triggers rupture of the Graafian follicle and release of the secondary oocyte (ovulation).

7. Q7medium

   At the time of birth, the oocytes in a human ovary are arrested at which stage of meiosis?

   • AMetaphase II
   • BProphase I of meiosis (primary oocyte)
   • CProphase II
   • DMeiosis fully completed
   Show answer & solution

   Correct answer: (B) Prophase I of meiosis (primary oocyte)

   Primary oocytes begin meiosis I during foetal life and are arrested at the prophase-I (diplotene) stage until they are recruited later, after puberty.

8. Q8hard

   The secondary oocyte completes its second meiotic division:

   • AJust before ovulation
   • BAt the onset of puberty
   • COnly after entry of the sperm (fertilization)
   • DIt is never completed
   Show answer & solution

   Correct answer: (C) Only after entry of the sperm (fertilization)

   The secondary oocyte is arrested at metaphase II and completes meiosis II only after a sperm enters it (fertilization), releasing the second polar body.

Want the full set? Practise all 15 Human Reproduction questions →