Previous year questions: Human reproduction

Previous year questions: human reproduction

This set carries six questions from actual CBSE board papers of the 2023, 2024, 2025 and 2026 exams, and four from official sample papers of the 2022-23 to 2025-26 sessions. Every heading gives the paper and the marks. Work the answer before reading it.

Q1 (CBSE Board 2023, 1 mark)

In which option does the endocrine gland correctly match its hormonal secretion and its function? (a) Sertoli cells, testosterone, development of secondary sexual characteristics. (b) Placenta, oestrogen, initiates secretion of milk. (c) Leydig cells, androgen, initiates the production of sperms. (d) Ovary, FSH, stimulates follicular development.

Answer: Option (c). Leydig cells lie in the interstitial spaces of the testis and secrete androgens, and the androgens start and maintain spermatogenesis. Sertoli cells do not make testosterone, the placenta does not initiate milk secretion through oestrogen, and FSH is a pituitary hormone, not an ovarian one.

Q2 (CBSE Board 2023, 5 marks)

A diagram of the menstrual cycle of a normal human female has day ranges marked. (i) Give the technical term for each range: days 1 to 7, days 8 to 12, days 16 to 28, days 13 to 15. (ii) Explain the role of ovarian and pituitary hormones during days 8 to 12, days 13 to 15 and days 16 to 28.

Answer: (i) Days 1 to 7 are the menstrual phase. Days 8 to 12 are the follicular or proliferative phase. Days 16 to 28 are the luteal or secretory phase, and days 13 to 15 are the ovulatory phase. (ii) Days 8 to 12: the pituitary raises FSH and LH gradually, the primary follicles grow towards the Graafian stage, and the growing follicles release oestrogen, which rebuilds the endometrium by proliferation. Days 13 to 15: LH reaches a mid-cycle peak called the LH surge, and the surge makes the Graafian follicle rupture and release the ovum. Oestrogen is at its peak here. Days 16 to 28: the remains of the follicle become the corpus luteum, which secretes progesterone. Progesterone maintains the endometrium for implantation, and it also suppresses FSH and LH. If fertilisation does not occur the corpus luteum degenerates, progesterone falls, the endometrium breaks down and menstruation begins.

Q3 (CBSE Board 2024, 5 marks)

The given diagram shows a sectional view of a seminiferous tubule of the human testis. (i) Name and describe the process depicted in the diagram that results in the development of spermatozoa. (ii) Identify the cell where a cluster of spermatozoa is attached in the diagram and write its function.

Answer: (i) The process is spermatogenesis. Spermatogonia near the wall of the tubule divide by mitosis and some of them become primary spermatocytes, which are diploid. The first meiotic division gives two haploid secondary spermatocytes, and the second meiotic division gives four haploid spermatids. Spermiogenesis remodels the spermatids into spermatozoa, and spermiation releases them into the lumen. The whole sequence depends on androgens from the Leydig cells and on factors from the Sertoli cells. (ii) The cell with the attached cluster of spermatozoa is the Sertoli cell. It nourishes and supports the developing germ cells and holds the sperm heads before their release.

Q4 (CBSE Board 2025, 1 mark)

A set of statements about spermatogenesis is given. (i) Sperm are released from the seminiferous tubules through spermiation. (ii) Spermiogenesis is the maturation of spermatids into sperm. (iii) Spermatogonia produce spermatids through spermiogenesis. (iv) Meiosis II in secondary spermatocytes gives four equal haploid spermatids. (v) A primary spermatocyte completes meiosis I to form two equal diploid cells called secondary spermatocytes. The options are (A) (i), (ii) and (iv); (B) (ii), (iii) and (v); (C) (ii), (iv) and (v); (D) (i), (iii) and (iv). Choose the option with all the true statements.

Answer: Statements (i), (ii) and (iv) are true, so the correct option is (A). Statement (iii) is false because spermatogonia reach spermatids through spermatogenesis, with meiosis in between; spermiogenesis only reshapes spermatids into sperms. Statement (v) is false because the secondary spermatocytes are haploid, not diploid.

Q5 (CBSE Board 2026, 1 mark)

The foetal ejection reflex in a human female triggers the release of which hormone? (A) Oxytocin from the foetal pituitary, (B) hCG from the placenta, (C) Progesterone from the corpus luteum, (D) Oxytocin from the maternal pituitary.

Answer: Option (D). The fully developed foetus and the placenta start mild uterine contractions, and this foetal ejection reflex causes the maternal pituitary to release oxytocin. Oxytocin then strengthens the uterine contractions. The foetal pituitary does not supply this hormone, hCG maintains the corpus luteum in early pregnancy, and progesterone supports the pregnancy but does not start labour.

Q6 (CBSE Board 2026, 5 marks)

Oogenesis is a discontinuous process that begins before birth and is completed after puberty. (i) Trace the development of a gamete mother cell until its release from the ovary during ovulation. (ii) Name the two pituitary hormones that play an important role in the process.

Answer: (i) The gamete mother cells, or oogonia, form in the fetal ovary and multiply by mitosis. They enter prophase I of meiosis and stop there as primary oocytes, each surrounded by a layer of granulosa cells to form a primary follicle. Many follicles degenerate, and those that survive become secondary follicles with more granulosa layers and a theca, and then tertiary follicles with a fluid-filled antrum. In the tertiary follicle the primary oocyte completes its first meiotic division unequally, giving a large secondary oocyte and a small first polar body. The follicle becomes the Graafian follicle, the secondary oocyte forms the zona pellucida around itself, and the follicle ruptures at ovulation to release the secondary oocyte. (ii) The two pituitary hormones are follicle stimulating hormone and luteinising hormone. FSH supports follicular growth, and the LH surge triggers ovulation.

Q7 (CBSE SQP 2022-23, 3 marks)

Explain the functions of these structures in the human male reproductive system: (a) scrotum, (b) Leydig cells, (c) male accessory glands.

Answer: (a) The scrotum holds the testes outside the abdominal cavity and keeps them about two to two and a half degrees below normal body temperature, which spermatogenesis needs. (b) Leydig cells lie in the interstitial spaces and synthesise and secrete androgens, and the androgens drive spermatogenesis and maintain the male accessory ducts and glands. (c) The seminal vesicles, prostate and bulbourethral glands secrete the seminal plasma, which supplies fructose, calcium and enzymes to the sperm, keeps them motile and lubricates the reproductive tract.

Q8 (CBSE SQP 2023-24, 2 marks)

Explain the hormonal regulation of spermatogenesis.

Answer: The hypothalamus puts out gonadotropin releasing hormone, and this makes the anterior pituitary secrete luteinising hormone plus follicle stimulating hormone. LH targets the Leydig cells, which respond by increasing androgen output, and those androgens stimulate spermatogenesis. FSH works on the Sertoli cells and prompts them to release factors that support spermiogenesis.

Q9 (CBSE SQP 2024-25, 3 marks)

Name the place in the human ovary where the first meiotic division is completed during oogenesis. What are the products of this division? Give the chromosome number of each type of cell involved.

Answer: The first meiotic division is completed in the tertiary follicle, after the follicle has formed its antrum. The division is unequal and gives two products: one large secondary oocyte and one small first polar body. The primary oocyte that starts the division has 46 chromosomes, and both products, the secondary oocyte and the first polar body, carry 23 chromosomes each.

Q10 (CBSE SQP 2025-26, 1 mark)

Formation of the Graafian follicle during the menstrual cycle is stimulated by which gonadotropin hormones? (A) Oestrogen and progesterone, (B) FSH and oestrogen, (C) FSH and LH, (D) Progesterone and LH.

Answer: Option (C), FSH and LH. Both gonadotropins rise through the follicular phase and stimulate follicular development, and their levels peak in the middle of the cycle. Oestrogen and progesterone are ovarian hormones, so options that pair them with the follicle's formation are wrong.

Six of these ten are printed board questions, spread over four board exam years. Look at how the two five-mark questions are built. The menstrual cycle question asks for names first and explanations second, and the oogenesis question asks for a traced pathway plus two hormones. Write the sequence, name each structure at the point where it appears, and give the ploidy wherever a cell is mentioned.