“Human Reproduction” MCQ with Answer Explanation : NEET 2025.

31. Which of the following structures forms the maternal part of the placenta?
    a) Chorion
    b) Endometrium
    c) Amnion
    d) Trophoblast

Answer: b) Endometrium

Explanation:
The maternal part of the placenta is derived from the endometrium, which is the inner lining of the uterus. The fetal part comes from the chorion, which originates from the trophoblast.

32. Which hormone is primarily responsible for the development of secondary sexual characteristics in females?
    a) Progesterone
    b) Oxytocin
    c) Estrogen
    d) Testosterone

Answer: c) Estrogen

Explanation:
Estrogen is the hormone that promotes the development of secondary sexual characteristics in females, such as breast development, widening of the hips, and the regulation of the menstrual cycle.

33. At which stage of human embryonic development does gastrulation occur?
    a) Blastocyst
    b) Morula
    c) Gastrula
    d) Zygote

Answer: c) Gastrula

Explanation:
Gastrulation occurs at the gastrula stage, where the embryo develops three germ layers: ectoderm, mesoderm, and endoderm. This process establishes the basic body plan of the organism.

34. Which of the following is the correct sequence of events during childbirth?
    a) Dilation → Expulsion → Placental stage
    b) Expulsion → Dilation → Placental stage
    c) Placental stage → Dilation → Expulsion
    d) Dilation → Placental stage → Expulsion

Answer: a) Dilation → Expulsion → Placental stage

Explanation:
Childbirth occurs in three stages: the dilation stage (where the cervix dilates to allow the baby to pass), the expulsion stage (delivery of the baby), and the placental stage (delivery of the placenta).

35. What is the primary function of the amniotic fluid?
    a) Nutrition of the fetus
    b) Protection of the fetus from mechanical injury
    c) Providing oxygen to the fetus
    d) Facilitating waste removal

Answer: b) Protection of the fetus from mechanical injury

Explanation:
Amniotic fluid surrounds the developing fetus in the amniotic sac, cushioning it from external shocks, maintaining a stable temperature, and allowing fetal movement for proper musculoskeletal development.

36. Which of the following cells undergoes the first meiotic division to produce secondary spermatocytes?
    a) Spermatogonia
    b) Primary spermatocyte
    c) Spermatid
    d) Spermatozoa

Answer: b) Primary spermatocyte

Explanation:
Primary spermatocytes undergo the first meiotic division to produce two haploid secondary spermatocytes. These then divide further in the second meiotic division to produce spermatids, which mature into spermatozoa (sperm).

37. Which of the following is a key role of FSH in the male reproductive system?
    a) Production of testosterone
    b) Stimulation of Sertoli cells for spermatogenesis
    c) Induction of ejaculation
    d) Maintenance of the epididymis

Answer: b) Stimulation of Sertoli cells for spermatogenesis

Explanation:
In males, follicle-stimulating hormone (FSH) stimulates the Sertoli cells, which are essential for supporting the process of spermatogenesis (sperm production). FSH, along with testosterone, ensures proper sperm development.

38. Which of the following is NOT a function of the placenta?
    a) Nutrient exchange
    b) Gas exchange
    c) Waste elimination
    d) Production of sperm

Answer: d) Production of sperm

Explanation:
The placenta plays a vital role in the exchange of nutrients, gases (oxygen and carbon dioxide), and waste products between the mother and the fetus. However, sperm production is a function of the male reproductive system, specifically the testes.

39. Which hormone is responsible for inhibiting FSH secretion to prevent the development of multiple follicles during the menstrual cycle?
    a) Inhibin
    b) Estrogen
    c) Progesterone
    d) LH

Answer: a) Inhibin

Explanation:
Inhibin is produced by the granulosa cells of the ovaries and inhibits the secretion of FSH (follicle-stimulating hormone). This helps regulate the menstrual cycle and prevents the development of multiple follicles.

40. Which of the following methods is used to detect fetal abnormalities early in pregnancy?
    a) Ultrasound
    b) Amniocentesis
    c) MRI
    d) X-ray

Answer: b) Amniocentesis

Explanation:
Amniocentesis is a diagnostic procedure used to detect chromosomal abnormalities and genetic disorders in the fetus by analyzing a sample of amniotic fluid. It is usually performed in the second trimester. Ultrasound is also commonly used for non-invasive fetal monitoring, but it does not provide genetic information.