Chapter 27 The Reproduction System Flashcards
The dartos and cremaster muscles are important to the integrity of the male reproductive system. Which of the following is true about the role they play?
A) They contract to push sperm along the ductus deferens.
B) They regulate the temperature of the testes.
C) They are responsible for penile erection.
D) They contract to allow ejaculation.
B) They regulate the temperature of the testes.
The ability of sperm cells to move along the ductus deferens is due to \_\_\_\_\_\_\_\_. A) gravity B) peristaltic contractions C) enzymatic activity D) hormonal action
B) peristaltic contractions
The ability of a male to ejaculate is due to the action of \_\_\_\_\_\_\_\_. A) parasympathetic nerves B) the dartos muscle C) luteinizing hormone D) the bulbospongiosus muscles
D) the bulbospongiosus muscles
The most important risk for testicular cancer in young males is \_\_\_\_\_\_\_\_. A) smoking B) a diet high in fat C) nondescent of the testes D) sexually transmitted infections
C) nondescent of the testes
Which of the following glands are responsible for 60% of the synthesis of semen? A) the seminal vesicles B) the bulbourethral glands C) the prostate D) the pituitary
A) the seminal vesicles
Which of the following hormones controls the release of anterior pituitary gonadotropins? A) LH B) FSH C) GnRH D) testosterone
C) GnRH
Development of male reproductive structures depends on which of the following events?
A) that the female hormones are suppressed during pregnancy
B) the suppression of inhibin
C) secretion of male hormones prenatally and lasting into the first few months after birth
D) that human gonadotropin be synthesized in the first week of the pregnancy
C) secretion of male hormones prenatally and lasting into the first few months after birth
The primary function of the uterus is to ________.
A) protect the ovaries
B) synthesize female hormones
C) regulate the ovarian and menstrual cycles
D) receive, retain, and nourish a fertilized ovum
D) receive, retain, and nourish a fertilized ovum
Why is the blood-testis barrier important?
A) because spermatozoa and developing cells produce surface antigens that are recognized as foreign by the immune system
B) because some blood contents are toxic to the spermatozoa
C) because immature sperm cells lose their motility when they encounter any blood component
D) Actually, the blood-testis barrier has no function.
A) because spermatozoa and developing cells produce surface antigens that are recognized as foreign by the immune system
The structures that receive the ovulated oocyte, providing a site for fertilization, are called the \_\_\_\_\_\_\_\_. A) Graafian follicles B) fallopian tubes C) infundibula D) fimbriae
B) fallopian tubes
If gametes were diploid like somatic cells, how many chromosomes would the zygote contain?
A) twice the diploid number, and with every succeeding generation, the chromosome number would continue to double and normal development could not occur
B) triple the diploid number, and with every succeeding generation, the chromosome number would continue to triple and normal development would not occur
C) half the diploid number with no change in development
D) There is no relationship between gametes and somatic cells.
A) twice the diploid number, and with every succeeding generation, the chromosome number would continue to double and normal development could not occur
Human egg and sperm are similar in that ________.
A) about the same number of each is produced per month
B) they have the same degree of motility
C) they have the same number of chromosomes
D) they are about the same size
C) they have the same number of chromosomes
The constancy of the chromosome number from one cell generation to the next is maintained through \_\_\_\_\_\_\_\_. A) mitosis B) meiosis C) cytokinesis D) DNA synthesis
B) meiosis
Fertilization generally occurs in the \_\_\_\_\_\_\_\_. A) ovary B) uterus C) vagina D) fallopian tubes
D) fallopian tubes
Spermiogenesis involves the ________.
A) formation of four haploid cells from a spermatogonium
B) movement of sperm in the female genital tract
C) formation of a functional sperm by the stripping away of superfluous cytoplasm
D) sequence of events in the rete testis
C) formation of a functional sperm by the stripping away of superfluous cytoplasm
All of the following can be considered male secondary sex characteristics except the ________.
A) development of body hair
B) lowering of the voice
C) development of testes as opposed to ovaries
D) increasing mass of the skeleton
C) development of testes as opposed to ovaries
In humans, separation of the cells at the two-cell state following fertilization may lead to the production of twins, which in this case would be \_\_\_\_\_\_\_\_. A) dizygotic B) identical C) fraternal D) of different sexes
B) identical
Characteristics of the mature sperm include the ________.
A) presence of two X chromosomes in approximately half the sperm
B) presence of Y chromosomes in approximately half the sperm
C) absence of an acrosome
D) absence of coiled mitochondria
B) presence of Y chromosomes in approximately half the sperm
How do the testes respond to exposure to excessive body warmth?
A) They move close to the pelvic cavity.
B) They move away from the pelvic cavity.
C) Excessive warmth has no effect on the testicles because of their location in the scrotum.
D) Excessive warmth is actually beneficial in that it speeds up the maturation of sperm.
B) They move away from the pelvic cavity.
Effects of estrogen include \_\_\_\_\_\_\_\_. A) increased oiliness of the skin B) deepening of the voice C) growth of the breasts at puberty D) growth of the larynx
C) growth of the breasts at puberty
Secretion of progesterone stimulates ________.
A) contraction of uterine muscles
B) preparation of the mammary glands for lactation
C) secretory activity of the uterine myometrium
D) development of the female secondary sex characteristics
B) preparation of the mammary glands for lactation
Which of the following statements about sperm is not true?
A) They contain very little cytoplasm or stored nutrients.
B) They are sluggish in an alkaline environment.
C) The acrosome is produced by the Golgi apparatus and contains hydrolytic enzymes.
D) The sperm midpiece consists of mitochondria spiraled tightly around the contractile filaments of the tail.
B) They are sluggish in an alkaline environment.