Anatomy Ii Ch. 27

Front 1

T or F:

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

Back 1

False

Front 2

T or F:

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

Back 2

False

Front 3

T or F:

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

Back 3

False

Front 4

T or F:

The scrotum contains the testes and spermatic chords

Back 4

True

Front 5

T or F:

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

Back 5

False

Front 6

T or F:

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

Back 6

True

Front 7

T or F:

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

Back 7

True

Front 8

T or F:

Erectile dysfuntion prevents ejaculation in most cases.

Back 8

False

Front 9

T or F:

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

Back 9

True

Front 10

T or F:

Spermiogenesis is the last stage of meiosis

Back 10

False

Front 11

T or F:

Sperm make up just 10% of semen volume

Back 11

True

Front 12

T or F:

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

Back 12

True

Front 13

T or F:

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

Back 13

False

Front 14

T or F:

The first haploid stage of spermatogenesis is prophase II

Back 14

True

Front 15

T or F:

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

Back 15

False

Front 16

The _______ is/are generally accepted as secondary sex characteristic

Back 16

enlargement of breasts

Front 17

Which of the following are primary sex organs?
A. Ova

B. Uterine tubes

C. breasts

D. Ovaries

E. Scent Gland

Back 17

D. Ovaries

Front 18

Which of the following is a secondary sex organ?
A. testis

B. Ovary

C. Vagina

D. Facial Hair

E. Distribution of body fat

Back 18

C. Vagina

Front 19

Gonads begin to develop ____ to _____ weeks after fertilization

Back 19

5 to 6 weeks

Front 20

The _____ determine/s whether an organism will be genetically male or female.

Back 20

Sperm

Front 21

The gene that codes for the testis-determining factor (TDF) is found in or on the _____ chromosome

Back 21

Y chromosome

Front 22

The penis is homologous to the _____

Back 22

clitoris

Front 23

The _________ is the gonad and the ______ is the gamete.

Back 23

Testis ; Sperm

Front 24

_____________ stimulates the descent of the testes.

Back 24

Testosterone

Front 25

The ______ is an example of the female external genitalia

Back 25

clitoris

Front 26

From their formation to ejaculation, sperm cells take the following pathway:

Back 26

Seminiferous tubule > rete testis > epididymis, ductus deferens > ejaculatory duct > urethra

Front 27

When it is cold, the _______ contracts and draws the testes closer to the body to keep them warm.

Back 27

Cremaster muscle

Front 28

The countercurrent heat exchanger that prevents arterial blood from overheating the testes is the ______________

Back 28

pampiniform plexus of veins

Front 29

The blood-testis barrier...

Back 29

prevents antibodies in the blood from getting to the germ cells

Front 30

By volume, most of the semen is produced in the _________

Back 30

Seminal vesicles

Front 31

_________ are not found in or around the seminiferous tubules

Back 31

Corpus carvenosum cells

Front 32

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 cavernosum

Back 32

B. Prostate gland(s)

Front 33

Why would an enlarged prostate gland interfere with urination?

Back 33

E. it compresses the urethra

Front 34

The __________ is/are the site(s) or sperm maturation and storage.

Back 34

Ductus epididymides

Front 35

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

Back 35

A. the bulbospongiosus muscle

Front 36

When do the testes start secreting testosterone?

Back 36

In the first trimester of fetal development

Front 37

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

Back 37

E. Testosterones

Front 38

Which of the following is an androgen?

A. estrogen

B. progesterone

C. Testosterone

D. luteinizing hormone

E. follicle-stimulating hormone

Back 38

C. Testosterone

Front 39

____________ stimulates the interstitial cells of the testes to secret __________

Back 39

luteinizing hormone ; testosterone

Front 40

Which hormone suppresses the spermatogenesis without affecting testosteron secretion?

A. gonadotropin-releasing hormone (GnRH)

B. testosterone itself

C. inhibin

D. luteinizing hormone

E. follicle-stimulating hormone

Back 40

C. Inhibin

Front 41

The _______ cells has/have no androgen receptors and do/does not respond to it.

Back 41

germ cells

Front 42

Testosterone inhibits....

Back 42

Gonadotropin-releasing hormone (GnRH) secretion

Front 43

Changes called male climacteric are a consequence of ___________

Back 43

Decreased secretion of testosterone

Front 44

In the process of spermiogenesis, ________ become __________

Back 44

Spermatids ; spermatozoa

Front 45

In meiosis, each parent cell produces

Back 45

four haploid cells

Front 46

As a result of spermatogenesis and spermiogenesis, the final cells produced are called __________, but they and all of the stages leading up to them can be called ________.

Back 46

Gametes ; germ cells

Front 47

At the end of meiosis I there are __________, whereas at the end of meiosis II there is/are ______________

Back 47

two haploid cells ; four haploid cells

Front 48

The most important role of meiosis in sexual reproduction is...

Back 48

That it prevents the chromosome number from doubling in each generation

Front 49

At what stage does a developing sperm cell begin to grow a tail?

Back 49

Spermatid

Front 50

Sperm cells get energy to power their movement from _______ contributed by the __________

Back 50

Fructose ; Seminal vesicles

Front 51

Male infertility (sterility) refers to...

Back 51

The inability to fertilize an egg

Front 52

The acrosome contains enzymes used to..

Back 52

penetrate barriers surrounding the ovum

Front 53

_________ have 46 chromosomes, whereas ______ have 23.

Back 53

Primary spermatocytes ; spermatids

Front 54

A sperm count any lower than ____ to ____ million sperm per ml of semen is usually associated with infertility (sterility)

Back 54

20 to 25

Front 55

Dilation of the ________ arteries causes the lacunae to fill with blood and the penis to become erect

Back 55

Deep arteries

Front 56

The orgasm-emission phase of the male sexual response is stimulated by...

Back 56

efferent sympathetic signals from the lumbar region of spinal cord

Front 57

Erection is an _________ reflex mediated predominantly by ____________ nerve fibers.

Back 57

Autonomic ; parasympathetic

Front 58

Heart rate, blood pressure, and respiratory rate peak during the ________

Back 58

climax

Front 59

Sildenafil (Viagra) prolongs erection by inhibiting _______ of ________

Back 59

degradation of cGMP