All Free Biology MCQs with Answers
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19,844 questions · page 791 of 993
- A. Sertoli cells
- B. Connective tissue cells
- C. Intestinal cells
- D. Mast cells
Explanation: Spermatozoa are nourished during their development by sertoli cells. Sertoli cells are a type of cell that lines the seminiferous tubules…
Correct answer: Sertoli cells15802. Number of spermatozoa that a single primary spermatocyte ultimately produces in spermatogenesis is
- A. One
- B. Four
- C. Two
- D. Eight
Explanation: A single primary spermatocyte ultimately produces 4 spermatozoa in spermatogenesis.This is because during spermatogenesis, a primary…
Correct answer: Four- A. At the beginning of the cycle
- B. About 20 days through the cycle
- C. About half way through the cycle
- D. At the end of the cycle
Explanation: The ovum or egg is released about halfway through the menstrual cycle, during ovulation.Ovulation is the process of the egg being released…
Correct answer: About half way through the cycle- A. Day 1
- B. Day 14
- C. Day 10
- D. Day 28
Explanation: Ovulation occurs on day 14 of a 28 day human ovarian cycle. This means that ovulation occurs halfway through the menstrual cycle.
Correct answer: Day 14- A. Corpus luteum
- B. Corpus albicans
- C. Corpus callosum
- D. Corpus spongiosum
Explanation: The endocrine part of the ovary after ovulation is the corpus luteum.The corpus luteum is a temporary endocrine gland that is formed from…
Correct answer: Corpus luteum- A. Estrogen
- B. Progesterone
- C. Relaxin
- D. Prolactin
Explanation: Progesterone is the hormone that prevents the production of ova during pregnancy.
Correct answer: Progesterone- A. Menstruation starts
- B. Menstruation stops and reproductive capacity is arrested
- C. Puberty begins
- D. None of the above
Explanation: Menopause is the stage in a woman's life when her ovaries stop producing eggs.
Correct answer: Menstruation stops and reproductive capacity is arrested- A. Haploid
- B. Triploid
- C. Diploid
- D. Polyploid
Explanation: The diploid spermatogonia undergoes mitosis to form diploid primary spermetocytes.
Correct answer: Diploid- A. Spermatids change into spermatozoa
- B. Dormant spermatozoa become active just before ejaculation
- C. Spermatogonia produce spermatids
- D. Spermetocytes give rise to spermatozoa
Explanation: Spermiogenesis is the last phase in the formation of spermatozoa. After spermiogenesis, mature spermatozoa are released from the…
Correct answer: Spermatids change into spermatozoa15810. Sperms move by their:
- A. Tail
- B. Mitochondria
- C. Cilia
- D. Acrosome
Explanation: Sperms move by the tail and the source of the motility and the driving energy is provided by the mitochondria.
Correct answer: Tail- A. Middle piece
- B. Principal piece of tail
- C. Head
- D. End piece of tail
Explanation: Microtubules form the axial filament and it contains the mitochondria spirally arranged in it.
Correct answer: Middle piece- A. Formation of ova
- B. Formation of spermatids
- C. Change of spermatid to spermatozoa
- D. Release of ova
Explanation: Gametogenesis is the process of formation of gametes. In males, it is known as spermatogenesis which is the formation of spermatozoa and…
Correct answer: Release of ova- A. Relaxin
- B. FSH
- C. Oxytocin
- D. Oestrogen
Explanation: The FSH stimulates the follicle cells to secrete estrogen a female sex organ.It stimulates the uterus to prepare for the implantation and…
Correct answer: Oestrogen- A. Premenstrual phase
- B. Proliferative phase
- C. Luteal phase
- D. Secretory phase
Explanation: This phase occurs earlier in the menstrual cycle, specifically in the days leading up to ovulation (around days 6-14).
Correct answer: Proliferative phase- A. FSH
- B. MSH
- C. STH
- D. LH
Explanation: During menopause, the level of estrogen in the blood decreases. Thus, estrogen can no longer inhibit the production of FSH and LH.
Correct answer: FSH- A. Head
- B. Entire sperm
- C. Middle piece
- D. Tail
Explanation: The middle piece of mammalian sperm cell possesses numerous mitochondria.
Correct answer: Middle piece- A. Estrogen
- B. Testosterone
- C. FSH
- D. ACTH
Explanation: Sertoli cells are the nurse cells which are associated with the cells of seminiferous tubules.
Correct answer: FSH15818. On which date is a woman most likely to ovulate if the first day of menstrual loss was 1st February?
- A. 5th February
- B. 28th February
- C. 14th February
- D. 1st March
Explanation: In a typical 28-day menstrual cycle, ovulation occurs around the 14th day.
Correct answer: 14th February- A. Menstruation ---> Ovulation ---> Fertilization ---> Implantation
- B. Menstruation ---> Ovulation ---> Implantation ---> Fertilization
- C. Ovulation ---> Menstruation ---> Fertilization ---> Implantation
- D. Ovulation ---> Menstruation ---> Implantation ---> Fertilization
Explanation: The menstrual cycle may be divided into three parts:The menstrual phase (flow of blood), which lasts about 5 days on average.The…
Correct answer: Ovulation ---> Menstruation ---> Fertilization ---> Implantation- A. Nurse cells
- B. Receptor cells
- C. Reproductive cells
- D. None of these
Explanation: Sertoli cells are the nurse cells which are associated with the cells of seminiferous tubules.
Correct answer: Nurse cells