Chapter 3: Human Reproduction – Very Short Answer Type Questions
CBSE Class 12 Biology – Very Short Answer Questions with Answers
Unit I: Reproduction | Chapter 3: Human Reproduction (NCERT Based)
Course & Examination Details
- Course: CBSE Class 12 Biology
- Prescribed By: Central Board of Secondary Education
- Syllabus Reference: NCERT
- Unit: Unit I – Reproduction
- Chapter: Chapter 3 – Human Reproduction
- Exam Relevance: CBSE Class 12 Board Examinations
CBSE Class 12 Biology Chapter 3 Very Short Answer Questions – Human Reproduction (NCERT)
Section A: Male Reproductive System
Q1. What is the function of the scrotum?
Ans: The scrotum maintains testes at a temperature about 2–2.5°C lower than body temperature, essential for normal spermatogenesis.
Q2. Name the primary male reproductive organ.
Ans: Testes are the primary male reproductive organs responsible for sperm production and secretion of male hormones.
Q3. What are seminiferous tubules?
Ans: Seminiferous tubules are highly coiled structures in testes where spermatogenesis occurs.
Q4. Name the cells that nourish developing sperms.
Ans: Sertoli cells provide nutrition and support to developing spermatogenic cells.
Q5. Which cells secrete testosterone?
Ans: Interstitial or Leydig cells secrete testosterone, regulating spermatogenesis and male secondary sexual characters.
Section B: Accessory Ducts and Glands
Q6. What is the role of epididymis?
Ans: Epididymis stores sperms temporarily and allows their maturation.
Q7. Name the duct that carries sperms from epididymis.
Ans: Vas deferens transports sperms from epididymis to the urethra.
Q8. What is seminal plasma?
Ans: Seminal plasma is the fluid formed by secretions of accessory glands that nourish and activate sperms.
Q9. Name one function of seminal vesicles.
Ans: Seminal vesicles secrete fructose-rich fluid that provides energy to sperms.
Q10. Which gland adds alkaline secretion to semen?
Ans: Prostate gland adds alkaline fluid that neutralises acidity and improves sperm motility.
Section C: Female Reproductive System
Q11. Name the primary female reproductive organ.
Ans: Ovaries are the primary female reproductive organs producing ova and female hormones.
Q12. What is the function of fimbriae?
Ans: Fimbriae collect the ovum released from ovary and guide it into the fallopian tube.
Q13. Where does fertilisation occur in humans?
Ans: Fertilisation occurs in the ampullary region of the fallopian tube.
Q14. Name the site of implantation.
Ans: Implantation occurs in the endometrium of the uterus.
Q15. What is the function of the uterus?
Ans: The uterus supports implantation, embryonic development, and foetal growth.
Section D: Gametogenesis
Q16. What is gametogenesis?
Ans: Gametogenesis is the process of formation of haploid gametes in gonads.
Q17. Define spermatogenesis.
Ans: Spermatogenesis is the formation of sperms from spermatogonia in seminiferous tubules.
Q18. When does spermatogenesis begin?
Ans: Spermatogenesis begins at puberty under hormonal control.
Q19. What is spermiogenesis?
Ans: Spermiogenesis is the differentiation of spermatids into mature sperms.
Q20. Define oogenesis.
Ans: Oogenesis is the formation of ova from oogonia in ovaries.
Section E: Menstrual Cycle
Q21. What is the average duration of menstrual cycle?
Ans: The menstrual cycle averages about 28 days in humans.
Q22. What happens during menstrual phase?
Ans: Shedding of uterine endometrium occurs due to reduced progesterone levels.
Q23. Name the hormone responsible for ovulation.
Ans: Luteinising hormone (LH) surge triggers ovulation.
Q24. What is corpus luteum?
Ans: Corpus luteum is a temporary endocrine structure formed from ruptured follicle after ovulation.
Q25. Which hormone maintains pregnancy initially?
Ans: Progesterone maintains uterine endometrium during early pregnancy.
Section F: Fertilisation and Implantation
Q26. Define fertilisation.
Ans: Fertilisation is the fusion of male and female gametes forming a diploid zygote.
Q27. What is a zygote?
Ans: A zygote is the first diploid cell formed after fertilisation.
Q28. What is implantation?
Ans: Implantation is attachment of blastocyst to uterine endometrium.
Q29. Name the hormone detected in pregnancy test kits.
Ans: Human chorionic gonadotropin (hCG) is detected in pregnancy tests.
Q30. Which part of blastocyst forms placenta?
Ans: Trophoblast forms the placenta.
Section G: Pregnancy and Embryonic Development
Q31. What is the gestation period in humans?
Ans: The gestation period in humans is approximately 280 days or nine months.
Q32. Name the organ connecting mother and foetus.
Ans: Placenta connects mother and foetus for exchange of materials.
Q33. Mention one function of placenta.
Ans: Placenta facilitates nutrition, respiration, and waste removal for the foetus.
Q34. Name the fluid surrounding the embryo.
Ans: Amniotic fluid surrounds the embryo, providing protection.
Q35. What is organogenesis?
Ans: Organogenesis is the formation of organs during embryonic development.
Section H: Parturition and Lactation
Q36. Define parturition.
Ans: Parturition is the process of childbirth involving expulsion of the foetus.
Q37. Which hormone induces uterine contractions during labour?
Ans: Oxytocin induces strong uterine contractions during parturition.
Q38. What is foetal ejection reflex?
Ans: Signals from foetus trigger oxytocin release, initiating childbirth.
Q39. What is lactation?
Ans: Lactation is the production and secretion of milk by mammary glands after childbirth.
Q40. Name the first milk secreted after birth.
Ans: Colostrum is the first milk secreted after birth.
Section I: Conceptual Understanding
Q41. Why is colostrum important?
Ans: Colostrum contains antibodies providing passive immunity to the newborn.
Q42. What is the role of relaxin hormone?
Ans: Relaxin relaxes pelvic ligaments and cervix during pregnancy.
Q43. Why does oogenesis produce polar bodies?
Ans: Polar bodies help retain maximum cytoplasm in ovum.
Q44. Which phase of menstrual cycle is progesterone dominant?
Ans: Progesterone is dominant during luteal phase.
Q45. Name the male copulatory organ.
Ans: Penis is the male copulatory organ.
Section J: Higher-Order Recall
Q46. Why is spermatogenesis temperature sensitive?
Ans: Higher temperature damages sperm development, reducing fertility.
Q47. What prevents polyspermy in humans?
Ans: Zona pellucida reaction prevents entry of additional sperms.
Q48. Which structure releases ovum during ovulation?
Ans: Mature Graafian follicle releases ovum.
Q49. What happens if implantation fails?
Ans: Menstruation occurs due to breakdown of endometrium.
Q50. State one significance of sexual reproduction in humans.
Ans: Sexual reproduction ensures genetic variation and species continuity.
CBSE Board Exam Note
These Very Short Answer Questions (20–30 words each) are strictly NCERT-based, aligned with CBSE Class 12 Biology board exam standards, and ideal for 1-mark questions and rapid revision.