Question 1

Which of these factors does NOT contribute to parturition?

Accepted Answer

Increased cortisol secretion actually decreases plasma progesterone levels, which is necessary for parturition to occur. Therefore, factor B does not contribute to parturition.

Question 2

What happens during oogenesis?

Accepted Answer

During oogenesis, one primary oocyte yields one mature ovum. This happens through meiosis I and meiosis II, resulting in the formation of one functional haploid ovum containing 23 chromosomes. Thousands of primary oocytes are formed during fetal development, but only a small number of these will mature and be released during a woman's reproductive years.

Question 3

Which of these statements correctly describes a secondary spermatocyte?

Accepted Answer

A secondary spermatocyte is formed through the process of meiosis I and is haploid, meaning it has half the number of chromosomes as the original parent cell. However, in meiosis I, the chromosomes are still duplicated, meaning there are still two sister chromatids attached at the centromere. It's not until meiosis II that the sister chromatids separate, resulting in haploid cells with unduplicated chromosomes.

Question 4

During spermatogenesis, one spermatogonium containing 46 chromosomes yields __________________

Accepted Answer

During spermatogenesis, one spermatogonium undergoes mitosis and meiosis to eventually produce four spermatozoa, each containing 23 chromosomes. However, the closest option to this process is A, which mentions 16 spermatozoa, as it implies multiple divisions, though the exact number is incorrect.

Question 5

What is the trophoblast of the blastocyst destined to become?

Accepted Answer

The trophoblast is the outer layer of cells in the blastocyst and it is destined to become the fetal portion of the placenta, which is responsible for the exchange of nutrients and waste products between the fetus and mother. The inner cell mass is the group of cells inside the blastocyst that will give rise to the embryo itself, including the fetus and the amniotic sac.

Question 6

A reduction in the secretion of what hormone may serve as the trigger for the onset of puberty?

Accepted Answer

The onset of puberty is often associated with a reduction in the secretion of melatonin. Melatonin is a hormone produced by the pineal gland that plays a role in regulating sleep-wake cycles and is thought to influence the timing of puberty. A decrease in melatonin levels is believed to be one of the factors that signals the body to initiate the pubertal process.

Question 7

Which statement does NOT describe erection?

Accepted Answer

Erection occurs due to the dilation of the arterioles supplying the sponge-like vascular spaces of the penis, which leads to an increase in blood flow and subsequent expansion of the penile tissue. This is mediated by the production of nitric oxide, which stimulates the production of cGMP, leading to smooth muscle relaxation in the penile arteries and trabeculae. The presence of sperm in the seminiferous tubules is not directly related to erection.

Question 8

Which statement does NOT describe GnRH?

Accepted Answer

GnRH is not stimulated by testosterone, but rather it stimulates the release of testosterone from the testes.

Question 9

Which of the following female structures has tissue composition similar to the penis?

Accepted Answer

The clitoris is the only female structure that has tissue composition similar to the penis. Both the clitoris and the penis are made up of erectile tissue and contain sensitive nerve endings. The cervix, fallopian tubes, and labia majora are all made up of different types of tissue and do not have the same structure as the penis.

Question 10

Which of these statements is NOT describing oxytocin?

Accepted Answer

Oxytocin is actually produced in the hypothalamus and then stored and released by the posterior pituitary gland, not produced there directly.

Question 11

How do birth control pills act as contraceptives?

Accepted Answer

Birth control pills work by inhibiting the secretion of GnRH, which in turn prevents the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). This prevents the maturation and release of an egg (ovulation), which is necessary for fertilization and pregnancy to occur.

Question 12

Which of the following statements does NOT correctly describe control of ovarian hormone secretion?

Accepted Answer

The statement that under the influence of estrogen from developing follicles, secretion of both FSH and LH continues to decline throughout the follicular phase is incorrect. In reality, estrogen stimulates the secretion of both FSH and LH, but at a certain threshold, it inhibits FSH secretion in a negative-feedback manner while continuing to stimulate LH secretion. Therefore, the correct statement would be: under the influence of estrogen from developing follicles, secretion of FSH declines while secretion of LH is maintained and ultimately stimulated.

Question 13

Which is the correct sequence of the structures sperm travels through prior to ejaculation?

Accepted Answer

Sperm travels from the epididymis to the ductus deferens, then to the ejaculatory duct, and finally through the urethra for ejaculation.

Question 14

During which phase of the uterine cycle is the secretion of progesterone at a significant level?

Accepted Answer

The secretory phase, which occurs after ovulation, is characterized by high levels of progesterone secretion from the corpus luteum. This hormone helps to thicken the endometrium and prepare it for possible implantation of a fertilized egg.

Question 15

Which of these statements does NOT describe the trophoblast?

Accepted Answer

The trophoblast is not destined to become the fetus, but rather the fetal portion of the placenta. The inner cell mass is destined to become the fetus.

Question 16

Which structure serves as a common passageway for two tracts in the male?

Accepted Answer

The urethra serves as a common passageway for both the urinary tract and the reproductive tract in males. The ductus deferens carries sperm from the epididymis to the ejaculatory duct, while the ejaculatory duct carries sperm and seminal fluid to the urethra. The ureter transports urine from the kidneys to the bladder and is not involved in reproductive function.

Question 17

When a woman is taking the contraceptive pill, or when she is pregnant, her levels of ovarian steroids and pituitary gonadotropins are most similar to those that normally occur during the _______________.

Accepted Answer

During pregnancy and while taking the contraceptive pill, the woman's levels of ovarian steroids and pituitary gonadotropins are most similar to those that occur during the luteal phase. The contraceptive pill contains hormones that prevent ovulation and maintain a consistent level of hormones throughout the cycle, mimicking the luteal phase. Similarly, during pregnancy, the corpus luteum continues to produce progesterone, maintaining the high levels present during the luteal phase.

Question 18

Where are the sperm cells stored for maturation?

Accepted Answer

Sperm cells are stored and matured in the epididymis, a long coiled tube located on top of each testicle.

Question 19

Which of the following does NOT occur during the follicular phase of the ovarian cycle?

Accepted Answer

During the follicular phase of the ovarian cycle, the follicles in the ovary are maturing and one dominant follicle will eventually release an egg during ovulation. This phase is characterized by estrogen secretion, which stimulates the thickening of the endometrial lining of the uterus during the proliferative phase of the uterine cycle. The menstrual phase of the uterine cycle occurs when the endometrial lining is shed if fertilization does not occur. Progesterone secretion occurs during the luteal phase of the ovarian cycle, which follows ovulation. Therefore, the correct answer is D, as progesterone secretion does not occur during the follicular phase of the ovarian cycle.

Question 20

Which of these statements pertains to FSH?

Accepted Answer

FSH (follicle-stimulating hormone) is an anterior pituitary hormone that stimulates antrum formation in developing ovarian follicles. It is responsible for the development and maturation of ovarian follicles in females.

Quiz 17: Energy Balance and Temperature Regulation