Sperm production works best at a temperature a few degrees below core body temperature.
Correct Answer
True
True. Spermatogenesis is most efficient at about 2 to 4 degrees Celsius below core temperature, which is why the testes hang outside the body cavity in the scrotum.
Category: Testis and Sperm
Question 2
In males, spermatogenesis normally stops permanently by about age 50.
Correct Answer
False
False. Spermatogenesis begins at puberty and continues throughout life, although sperm counts gradually decline with age.
Category: Testis and Sperm
Question 3
The acrosome of a sperm cell contains enzymes that help it penetrate the outer coverings of the oocyte.
Correct Answer
True
True. The acrosome is a caplike vesicle over the sperm nucleus, and its enzymes digest a path through the layers surrounding the oocyte.
Category: Testis and Sperm
Question 4
The meiotic divisions of spermatogenesis produce diploid spermatids.
Correct Answer
False
False. Meiosis halves the chromosome number, so spermatids are haploid with 23 chromosomes, which lets fertilization restore the diploid number of 46.
Category: Testis and Sperm
Question 5
Tight junctions between Sertoli cells form the blood-testis barrier.
Correct Answer
True
True. Sertoli cells are joined by tight junctions that create the blood-testis barrier, protecting developing sperm from the immune system and from substances in the blood.
Category: Testis and Sperm
Question 6
Testosterone stimulates the hypothalamus to increase its release of GnRH.
Correct Answer
False
False. Testosterone exerts negative feedback, inhibiting GnRH release from the hypothalamus and LH release from the anterior pituitary.
Category: Reproductive Hormones
Question 7
The number of oocytes in the ovaries declines between birth and puberty.
Correct Answer
True
True. A newborn's ovaries hold roughly 1 to 2 million oocytes, but atresia steadily eliminates them, leaving about 400,000 by puberty and essentially none by menopause.
Category: Oogenesis and Ovarian Cycle
Question 8
Each primary oocyte that completes oogenesis yields four functional ova.
Correct Answer
False
False. The cytoplasm divides unequally in oogenesis, so each primary oocyte yields only one ovum, while the small polar bodies degenerate.
Category: Oogenesis and Ovarian Cycle
Question 9
A secondary oocyte completes meiosis II only if a sperm penetrates it.
Correct Answer
True
True. The ovulated secondary oocyte remains paused in meiosis II, and sperm entry is the signal that lets it finish division and become a mature ovum.
Category: Oogenesis and Ovarian Cycle
Question 10
If pregnancy does not occur, the corpus luteum degenerates into the corpus albicans.
Correct Answer
True
True. Without signals from an implanted embryo, the corpus luteum breaks down after about 10 to 12 days, leaving a nonfunctional scar called the corpus albicans.
Category: Oogenesis and Ovarian Cycle
Question 11
A sharp rise in progesterone triggers the start of menstruation.
Correct Answer
False
False. Menstruation begins when progesterone falls as the corpus luteum degenerates, which causes the stratum functionalis to break down and shed.
Category: Reproductive Hormones
Question 12
Sustained high estrogen from the dominant follicle exerts positive feedback that increases LH release.
Correct Answer
True
True. Low or early estrogen levels inhibit gonadotropins, but sustained high estrogen from a mature follicle switches to positive feedback and produces the LH surge.
Category: Reproductive Hormones
Question 13
The isthmus is the funnel-shaped end of the uterine tube that lies nearest the ovary.
Correct Answer
False
False. The funnel-shaped end near the ovary is the infundibulum, which bears the fimbriae; the isthmus is the narrow segment that joins the uterus.
Category: Female Reproductive Anatomy
Question 14
The myometrium is the thick layer of smooth muscle in the uterine wall.
Correct Answer
True
True. The myometrium is the middle and thickest layer of the uterus, and its smooth muscle contracts strongly during labor.
Category: Female Reproductive Anatomy
Question 15
A healthy vagina normally has an alkaline pH.
Correct Answer
False
False. Lactobacillus bacteria produce lactic acid that keeps the healthy vaginal pH acidic, below about 4.5, which helps protect against pathogens.
Category: Female Reproductive Anatomy
Question 16
Menopause is confirmed after 12 consecutive months without a menstrual period.
Correct Answer
True
True. Menopause marks the end of menstrual cycles after the ovarian follicles are depleted, and it is identified once a full year has passed without menses.
Category: Reproductive Hormones
Question 17
In a male embryo, the Mullerian ducts degenerate because of secretions from Sertoli cells.
Correct Answer
True
True. Sertoli cells in the developing testis release a factor that causes the Mullerian ducts to break down, so female internal structures do not form.
Category: Reproductive Development
Question 18
Breast size determines how much milk a woman can produce.
Correct Answer
False
False. Breast size depends mainly on the amount of adipose tissue, not on the milk-secreting glandular tissue, so it does not determine milk output.
Category: Female Reproductive Anatomy
Question 19
Puberty begins when the pulses of GnRH from the hypothalamus decrease.
Correct Answer
False
False. Puberty starts when GnRH pulses increase, raising LH and FSH output, which stimulates the gonads to mature and secrete sex steroids.
Category: Reproductive Development
Question 20
Penile erection results from constriction of the arteries that supply the erectile tissue.
Correct Answer
False
False. Erection occurs when nitric oxide dilates the arteries supplying the erectile tissue, so blood fills the spaces and compresses the veins that drain them.
Category: Testis and Sperm