Review Chapter 27

________________ stimulates the descent of the testes. A. The presence of Y chromosome B. The presence of the X chromosome C. The absence of the X chromosome D. Testosterone E. Estrogens

Testosterone

Erection is A. an autonomic reflex mediated predominantly by parasympathetic nerve fibers. B. an autonomic reflex mediated predominantly by sympathetic nerve fibers. C. a somatic reflex mediated predominantly by parasympathetic nerve fibers. D. a somatic reflex mediated predominantly by sympathetic nerve fibers. E. an exclusively voluntary action mediated by the cerebral cortex.

an autonomic reflex mediated predominantly by parasympathetic nerve fibers.

This image shows a section of the testis and scrotal contents. What does "2" represent? A. spermatic cord B. epididymis C. rete testis D. seminiferous tubules E. ductus (vas) deferens

ductus (vas) deferens

This image shows spermatogenesis. What does "3" represent? A. spermatogonium B. secondary spermatocyte C. primary spermatocyte D. spermatid E. sperm

secondary spermatocyte

The _____________ is the gonad and the ___________ is the gamete. A. testis; ovary B. testis; semen C. testis; sperm D. sperm; semen E. semen; sperm

testis; sperm

Which of the following hormones directly stimulates the development of male secondary sex characteristics? A. estrogen B. inhibin C. luteinizing hormone D. follicle stimulating hormone E. testosterone

testosterone

Which of the following is an androgen? A. estrogen B. progesterone C. testosterone D. luteinizing hormone (LH) E. follicle-stimulating hormone (FSH)

testosterone

A sperm count any lower than ___________ million sperm per mL of semen is usually associated with infertility (sterility). A. 250 to 500 B. 200 to 250 C. 100 to 200 D. 50 to 100 E. 20 to 25

20 to 25

Gonads begin to develop A. 2 to 3 weeks after fertilization. B. 5 to 6 weeks after fertilization. C. 8 to 9 weeks after fertilization. D. 20 to 24 weeks after fertilization. E. at birth.

5 to 6 weeks after fertilization.

_____________ are not found in or around the seminiferous tubules. A. Interstitial (Leydig) cells B. Germ cells C. Sustentacular (Sertoli) cells D. Spermatids E. Corpus cavernosum cells

Corpus cavernosum cells

Erectile dysfunction prevents ejaculation in most cases.

False

Myotonia of skeletal muscles is characteristic of the excitement phase and refractory period.

False

Sexual reproduction entails the union of two gonads to form a zygote.

False

Sperm travels along the ductus deferens before reaching the spermatic cord.

False

Spermiogenesis is the last stage of meiosis.

False

Sympathetic nerve fibers trigger the secretion of nitric oxide, which dilates the deep arteries allowing blood to engorge the penis

False

The mechanism that keeps the testes cooler than the body's core temperature is called descent of the testes.

False

Why would an enlarged prostate gland interfere with urination? A. It inhibits urine production. B. It develops calcified deposits that block the urethra. C. It produces thicker prostatic secretions that block the urethra. D. It inhibits the micturition reflex. E. It compresses the urethra.

It compresses the urethra.

_____________ stimulates the interstitial cells of the testes to secrete __________. A. Gonadotropin-releasing hormone (GnRH); LH B. Follicle-stimulating hormone (FSH); androgen-binding protein (ABP) C. Luteinizing hormone (LH); androgen-binding protein (ABP) D. Luteinizing hormone (LH); testosterone E. Luteinizing hormone (LH); estrogen

Luteinizing hormone (LH); testosterone

_________ have 46 chromosomes, whereas _____________ have 23. A. Spermatids; spermatozoa B. Primary spermatocytes; spermatids C. Secondary spermatocytes; primary spermatocytes D. Spermatogonia; primary spermatocytes E. Type A spermatogonia; type B spermatogonia

Primary spermatocytes; spermatids

_________ is/are generally accepted as a secondary sex characteristic. A. The enlargement of the breasts B. The presence of testes C. The prostate gland D. The uterus E. The vagina

The enlargement of the breasts

_____________ determine/s whether an organism will be genetically male or female. A. Hormonal, genetic and environmental factors B. Prenatal hormone exposure C. The egg D. The sperm E. Both egg and sperm equally

The sperm

At early puberty, follicle stimulating hormone (FSH) and luteinizing hormone (LH) stimulate enlargement of the testes.

True

Only germ cells undergo meiosis, which produces four haploid cells with 23 chromosomes each

True

Sperm make up just 10% of semen volume.

True

Sustentacular cells secrete inhibin, which regulates the rate of sperm production

True

Testosterone stimulates development of the secondary sex characteristics, spermatogenesis, and libido.

True

The first haploid stage of spermatogenesis is prophase II.

True

The presence of the Y chromosome guarantees the development of male secondary sex organs.

True

The scrotum contains the testes and spermatic cords

True

The most important role of meiosis in sexual reproduction is A. that it reduces the size of the gametes. B. that it produces at least one gamete that is mobile. C. that it prevents the chromosome number from doubling in each generation. D. that it ensures that each daughter cell doubles the number of chromosomes. E. that it changes the genetic composition of each chromosome.

that it prevents the chromosome number from doubling in each generation.

This image shows a sagittal section of the male reproductive system. What does "4" represent? A. seminal vesicle B. urethra C. bulbourethral gland D. prostate gland E. ejaculatory duct

bulbourethral gland

The gene that codes for the testis-determining factor (TDF) is found in or on A. the Y chromosome. B. the X chromosome. C. the gonadal ridges. D. the fetal testes. E. the mesonephros.

the Y chromosome.

All of the following play a role in thermoregulation of the testes except A. the bulbospongiosus muscle. B. the cremaster muscle. C. the pampiniform plexus of veins. D. the countercurrent heat exchanger. E. the dartos muscle.

the bulbospongiosus muscle.

The penis is homologous to A. the appendix. B. a finger. C. the urethra. D. the vagina. E. the clitoris.

the clitoris.

Male infertility (sterility) refers to A. the inability to fertilize an egg. B. low sperm count. C. a lack of seminal fluid during ejaculation. D. low levels of testosterone. E. the inability to have an erection.

the inability to fertilize an egg.

The countercurrent heat exchanger that prevents arterial blood from overheating the testes is A. the rete testis. B. the epididymis. C. the pampiniform plexus of veins. D. the blood-testis barrier. E. the scrotal portal system.

the pampiniform plexus of veins.

At the end of meiosis I there are ____________, whereas at the end of meiosis II there is/are _____________. A. two diploid cells; one diploid cell B. two diploid cells; one haploid cell C. two diploid cells; four haploid cells D. two haploid cells; four haploid cells E. two haploid cells; one diploid cell

two haploid cells; four haploid cells

Which of the following is a secondary sex organ? A. testis B. ovary C. vagina D. facial hair E. distribution of body fat

vagina

Heart rate, blood pressure, and respiratory rate peak during the A. excitement phase. B. erection of the penis. C. climax (orgasm). D. plateau phase. E. resolution phase.

climax (orgasm).

The _______________ is an example of the female external genitalia. A. scrotum B. clitoris C. uterine tube D. seminal vesicle E. vagina

clitoris

This image shows a sagittal section of the male reproductive system. What does "3" represent? A. epididymis B. corpus spongiosum C. corpus cavernosum D. scrotum E. ductus (vas) deferens

corpus spongiosum

The penile urethra is enclosed by the A. corpus cavernosum. B. corpus spongiosum. C. trabecular muscle. D. prepuce. E. frenulum.

corpus spongiosum.

When it is cold, the _____________ contracts and draws the testes closer to the body to keep them warm. A. cremaster muscle B. pampiniform plexus C. corpus spongiosum D. perineum E. corpus cavernosum

cremaster muscle

Dilation of the ______________ causes the lacunae to fill with blood and the penis to become erect. A. helicine arteries B. internal pudendal (penile) arteries C. dorsal arteries D. dorsal veins E. deep arteries

deep arteries

The _____________ is/are the site(s) of sperm maturation and storage. A. seminiferous tubules B. rete testis C. prostate gland D. ductus epididymides E. seminal vesicles

ductus epididymides

The orgasm-emission phase of the male sexual response is stimulated by A. efferent sympathetic signals from the sacral region of the spinal cord. B. efferent sympathetic signals from the lumbar region of the spinal cord. C. efferent parasympathetic signals from the sacral region of the spinal cord. D. efferent parasympathetic signals from the lumbar region of the spinal cord. E. efferent somatic signals from the thoracic region of the spinal cord.

efferent sympathetic signals from the lumbar region of the spinal cord.

In meiosis, each parent cell produces A. two haploid cells. B. four haploid cells. C. two diploid cells. D. four diploid cells. E. haploid cells identical to the parent cell.

four haploid cells.

Sperm cells get energy to power their movement from _________ contributed by the ____________. A. prostaglandins; prostate gland B. sucrose; bulbourethral gland C. fructose; seminal vesicles D. seminogelin; prostate gland E. semen; seminiferous gland

fructose; seminal vesicles

As a result of spermatogenesis and spermiogenesis, the final cells produced are called ____________, but they and all the stages leading up to them can be called ____________. A. sperm cells; interstitial cells B. sperm cells; sustentacular cells C. secondary spermatocytes; spermatocytes in general D. secondary spermatocytes; germ cells E. gametes; germ cells

gametes; germ cells

The ______________ has/have no androgen receptors and do/does not respond to it. A. germ cells B. muscular tissue C. sustentacular cells D. hypothalamus E. pituitary gland

germ cells

Testosterone inhibits A. libido. B. development of secondary sex organs. C. development of secondary sex characteristics. D. gonadotropin-releasing hormone (GnRH) secretion. E. sperm production.

gonadotropin-releasing hormone (GnRH) secretion.

When do the testes start secreting testosterone? A. in the first trimester of fetal development B. in the first trimester after birth C. in the first three years after birth D. in the first three years of adolescence E. after the first ejaculation

in the first trimester of fetal development

Changes called male climacteric are a consequence of A. increased secretion of estrogens. B. increased secretion of progesterone. C. decreased secretion of testosterone. D. increased secretion of FSH and LH. E. increased secretion of GnRH.

increased secretion of FSH and LH.

Which hormone suppresses spermatogenesis without affecting testosterone secretion? A. gonadotropin-releasing hormone (GnRH) B. testosterone itself C. inhibin D. luteinizing hormone (LH) E. follicle-stimulating hormone (FSH)

inhibin

Sildenafil (Viagra) prolongs erection by A. activating nitric oxide (NO) production. B. inactivating guanylate cyclase. C. stimulating production of cGMP. D. inhibiting degradation of cGMP. E. inhibiting nitric oxide (NO) production.

inhibiting degradation of cGMP.

Which of the following are primary sex organs? A. ova B. uterine tubes C. breasts D. ovaries E. scent glands

ovaries

The acrosome contains enzymes used to A. dissolve the mucosa of the vagina. B. dissolve the mucosa of the uterus. C. dissolve the stickiness of the semen. D. penetrate the vagina. E. penetrate barriers surrounding the ovum.

penetrate barriers surrounding the ovum.

The blood-testis barrier A. prevents antibodies in the blood from getting to the germ cells. B. prevents heat loss from the testes. C. prevents blood from getting to the testes. D. maintains testis temperature at 35°C. E. maintains testis temperature at 37°C.

prevents antibodies in the blood from getting to the germ cells.

This image shows a sagittal section of the male reproductive system. What does "3" represent? A. seminal vesicle B. urethra C. bulbourethral gland D. prostate gland E. ejaculatory duct

prostate gland

Men have only one ____________ but have two of all the rest of these. A. bulbourethral gland(s) B. prostate gland(s) C. ejaculatory duct(s) D. seminal vesicle(s) E. corpus(ora) cavernosum(a)

prostate gland(s)

By volume, most of the semen is produced in the A. testes. B. penis. C. prostate gland. D. seminal vesicles. E. bulbourethral glands.

seminal vesicles.

From their formation to ejaculation, sperm cells take the following pathway: A. seminiferous tubule, epididymis, rete testis, urethra, ejaculatory duct, ductus deferens. B. seminiferous tubule, epididymis, rete testis, ejaculatory duct, ductus deferens, urethra. C. seminiferous tubule, epididymis, rete testis, ductus deferens, ejaculatory duct, urethra. D. seminiferous tubule, rete testis, epididymis, ductus deferens, ejaculatory duct, urethra. E. seminiferous tubule, rete testis, epididymis, ejaculatory duct, urethra, ductus deferens

seminiferous tubule, rete testis, epididymis, ductus deferens, ejaculatory duct, urethra.

At what stage does a developing sperm cell begin to grow a tail? A. spermatozoon B. spermatid C. primary spermatocyte D. secondary spermatocyte E. spermatogonium

spermatid

In the process of spermiogenesis, ___________ become ___________. A. spermatocytes; spermatozoa B. spermatozoa; spermatids C. spermatogonia; spermatocytes D. spermatocytes; spermatids E. spermatids; spermatozoa

spermatids; spermatozoa