Question 1

Which of the following best describes the role of Sertoli cells in spermatogenesis?

Accepted Answer

They protect germ cells from toxic substances in the blood and produce inhibin to regulate FSH.

Question 2

During oogenesis, why are the two cells produced by the first meiotic division unequal in size?

Accepted Answer

The secondary oocyte receives more cytoplasm to support early development after fertilization.

Question 3

Which hormone is primarily responsible for stimulating Leydig cells to produce testosterone in males?

Accepted Answer

LH (Luteinizing Hormone)

Question 4

What is the function of the acrosome cap on a sperm cell?

Accepted Answer

It contains digestive enzymes to penetrate the protective layers of the egg.

Question 5

Which equation correctly represents the chromosome number change during spermatogenesis?

Accepted Answer

$$2n \rightarrow n$$

Question 6

What triggers the completion of the second meiotic division in the secondary oocyte?

Accepted Answer

Fertilization by a sperm cell

Question 7

Why is the scrotum located outside the body cavity in males?

Accepted Answer

To maintain a temperature slightly below body temperature, which is optimal for spermatogenesis.

Question 8

Which of the following is a direct effect of high levels of estrogen around day 12 of the ovarian cycle?

Accepted Answer

Positive feedback on the pituitary, causing a surge in LH and FSH.

Question 9

What is the primary function of the corpus luteum after ovulation?

Accepted Answer

To produce estrogen and progesterone for endometrial maintenance.

Question 10

Which process ensures that only one sperm fertilizes an egg in mammals?

Accepted Answer

Blocks to polyspermy, including membrane depolarization and formation of the fertilization envelope.

Question 11

If fertilization does NOT occur, what hormonal changes lead to menstruation?

Accepted Answer

Decrease in estrogen and progesterone levels due to degeneration of the corpus luteum.

Question 12

Which structure in the female reproductive system is the usual site of fertilization?

Accepted Answer

Oviduct (Fallopian tube)

Question 13

What is the role of inhibin in the male reproductive system?

Accepted Answer

It inhibits the secretion of FSH by the anterior pituitary.

Question 14

Which hormone is detected by ovulation tests to predict the timing of ovulation?

Accepted Answer

LH

Question 15

RU-486 (mifepristone) acts as a mimic of which hormone, and what is its effect?

Accepted Answer

Progesterone; it blocks progesterone receptors, leading to menstruation.

Question 16

Which of the following best explains why sperm motility is low under acidic conditions?

Accepted Answer

Sperm motility is activated by neutral or slightly basic pH, which is optimal for flagellar movement.

Question 17

Which feedback mechanism is responsible for the surge in LH and FSH that triggers ovulation?

Accepted Answer

Positive feedback by high levels of estrogen on the pituitary.

Question 18

What is the main function of the endometrium during the uterine cycle?

Accepted Answer

To build up and prepare for the arrival of a blastocyst, then break down if fertilization does not occur.

Question 19

Which of the following is a consequence of the blastocyst secreting human chorionic gonadotropin (hCG) after implantation?

Accepted Answer

The corpus luteum is maintained, continuing to produce progesterone and estrogen to support pregnancy.

Question 20

Which equation best represents the hormonal feedback loop controlling the ovarian cycle?

Accepted Answer

$$	ext{GnRH} ightarrow 	ext{FSH/LH} ightarrow 	ext{Estrogen/Progesterone}$$

Gametogenesis and Fertilization: Spermatogenesis, Oogenesis, and Hormonal Regulation

Study Guide - Practice Questions