All Free Biology MCQs with Answers

1971. The human sperm was first discovered by ___________?

• A. Anton van Leeuwenhoek
• B. Von Baer
• C. Robert Hook
• D. None of These

Explanation: Anton van Leeuwenhoek first observed human sperm cells in semen using a microscope in the seventeenth century. Von Baer is associated with embryological discoveries, while Robert Hooke described cells, so either is a likely historical distractor.

1972. The Process of egg formation in the female is called ________?

• A. oocyte
• B. oogenesis
• C. Oviduct
• D. None of these

Explanation: Oogenesis is the complete process by which female germ cells develop into ova, including growth and maturation of oocytes. An oocyte is a developing egg cell, not the name of the formation process, so students may choose option a by confusing a cell with the process producing it.

1973. The process in which a sperm joins with an egg is__________?

• A. Pollination
• B. Respiration
• C. Fertilization
• D. Asexual reproduction

Explanation: Fertilization is the fusion of a sperm nucleus with the egg nucleus, producing a diploid zygote. Students may choose asexual reproduction because it also produces offspring, but asexual reproduction does not involve the joining of sperm and egg.

1974. The doctor who helps in the delivery of babies is an ___________?

• A. Obstetrician
• B. Gynecologist
• C. Pediatrician
• D. Podiatrist

Explanation: An obstetrician specialises in pregnancy, labour and delivery, including the medical care of the mother and baby during childbirth. A gynecologist treats the female reproductive system more broadly, so students may choose that option when they overlook the specific focus on delivery.

1975. Self pollination is not possible in ________ ?

• A. Dioecious plants
• B. Pawpaw
• C. Flowers
• D. both A and B Educational Resources

Explanation: Self-pollination cannot occur in dioecious plants because male and female flowers are present on separate plants; pawpaw is a commonly cited dioecious plant. The likely trap is c, because the word “flowers” is too general, whereas many flowers are bisexual and can self-pollinate.

1976. The foetus is protected from the mechanical damage by the__________?

• A. cervix
• B. vagina
• C. uterus
• D. amniotic fluid

Explanation: Amniotic fluid surrounds the foetus and absorbs shocks, thereby protecting it from mechanical injury while also allowing movement. The uterus contains and supports the foetus, but the fluid provides the main cushioning effect; the cervix and vagina do not act as shock absorbers.

1977. The first stage of development in which a cavity appears is the__________?

• A. Neurula
• B. Morula
• C. Gastrula
• D. Balastula

Explanation: The blastula is the first embryonic stage in which a fluid-filled cavity called the blastocoel appears. A student may choose morula by confusing the first solid ball of cells with the later hollow blastula.

1978. The cells present in testes and secrete testosterone are___________?

• A. Sertoli cells
• B. Germinal cell
• C. Interstitial cells
• D. Spermatocyte

Explanation: Interstitial cells, also called Leydig cells, lie between the seminiferous tubules and produce testosterone in response to luteinising hormone. The likely mistake is Sertoli cells, which nourish developing sperm and support spermatogenesis but do not secrete the main testicular androgen.

1979. Adult birds normally possess only one functional____________?

• A. Ureter
• B. Ovary
• C. Lung
• D. Testis

Explanation: Female birds normally retain only the left ovary and left oviduct as functional, while the right side is greatly reduced, an adaptation that reduces body mass for flight. Students may choose one functional testis because some birds have asymmetry in reproductive organs, but the standard general statement concerns the ovary.

1980. Double fertilization occurs in_________?

• A. All plants
• B. All seed plants
• C. Gymnosperms
• D. Angiosperms

Explanation: Double fertilization is characteristic of angiosperms: one sperm fertilizes the egg to form the zygote, while the other fuses with the polar nuclei to form the triploid endosperm. Students may choose all seed plants because both gymnosperms and angiosperms produce seeds, but gymnosperms do not show typical double fertilization.