Deck 20: Reproduction

Question 1

How many chromosomes are found in a normal human cell?

A)23
B)23 pair
C)46
D)Both 23 pair and 46 are correct.

Answer 1

D

Question 2

Leydig cells in the male produce Müllerian inhibition factor.

Answer 2

False

Question 3

Dihydrotestosterone is produced by the action of the enzyme 5 alpha-reductase on testosterone.

Answer 3

True

Question 4

A fertilized egg is called a/an

A)autosome.
B)zygote.
C)ovum.
D)Barr body.

Question 5

What is the principal sex steroid in males?

A)estrogen
B)testosterone
C)progesterone
D)aldosterone

Question 6

Female accessory organs develop because of the presence of ovaries.

Question 7

Treating a male fetus with antibodies to DHT would prevent development of the epididymides.

Question 8

Female accessory sex organs develop from the mesonephric ducts.

Question 9

How many autosomal chromosomes are present in human cells?

A)23 pair
B)46
C)22 pair
D)2 pair

Question 10

Deletion of the SRY gene would cause male fetuses to develop as females.

Question 11

Which of the following would be found in normal somatic cells of women but not men?

A)an X chromosome
B)a Y chromosome
C)a Barr body
D)22 pairs of autosomal chromosomes

Question 12

Genomic imprinting allows for differing expressions of an allele.

Question 13

Epigenetic changes cannot be passed on to a zygote.

Question 14

What type of genetic change occurs when an allele is silenced by methylation of cytosine bases?

A)genomic
B)epigenetic
C)mutation
D)None of the choices is correct.

Question 15

Regions of DNA that read the same forward as backward are called ______ and include the testis-specific genes on the Y chromosome.

A)palindromes
B)autosomes
C)haploid
D)genomic

Question 16

What type of genes are found on the Y chromosome?

A)X-transposed genes
B)degenerate genes
C)testis-specific genes
D)All of the choices are correct.

Question 17

Barr bodies are normally only found in the cells of female mammals.

Question 18

Patients with Turner's syndrome have 47 chromosomes and appear female.

Question 19

Cryptorchid males do not produce testosterone.

Question 20

The human female determines the sex of her offspring.

Question 21

In general,the onset of puberty occurs sooner in boys compared to girls.

Question 22

The secretion of GnRH,FSH,and LH are pulsatile instead of continuous.

Question 23

Testosterone,not DHT,stimulates embryonic development of

A)seminal vesicles.
B)ductus deferens.
C)ejaculatory duct.
D)All of the choices are correct.

Question 24

During the first trimester of pregnancy,the ovaries are active endocrine glands.

Question 25

The first event to occur during development of the reproductive system would be the

A)descent of the testes into the scrotum.
B)formation of the vagina.
C)onset of testosterone production.
D)development of the Müllerian ducts.

Question 26

Gonadotropic hormones from the anterior pituitary will affect the gonads in all of the following ways EXCEPT

A)stimulation of spermatogenesis or oogenesis.
B)stimulation of gonadal hormone secretion.
C)development of internal genital ducts.
D)maintenance of gonad structures.

Question 27

Those with testicular feminization syndrome have

A)an extra X chromosome.
B)a missing X chromosome.
C)an extra chromosome 23.
D)no chromosomal number abnormalities.

Question 28

Males lacking testosterone receptors would

A)develop as genotypic females.
B)have testes and female external genitalia.
C)lack gonads.
D)have male internal genitalia.

Question 29

What event(s)occur to start puberty?

A)GABA release in hypothalamus is reduced.
B)Glutamate stimulation of the hypothalamus is increased.
C)Increased secretion of GnRH to the anterior pituitary.
D)All of the choices are correct.

Question 30

Inhibin prevents release of LH from the anterior pituitary.

Question 31

Testosterone levels in the male embryo and fetus are very high throughout the prenatal period.

Question 32

The first sign of puberty in females is

A)breast development.
B)menarche.
C)growth spurt.
D)axillary hair.

Question 33

The most common cause of female pseudohermaphroditism is congenital adrenal hyperplasia.

Question 34

The rate at which GnRH is secreted from the hypothalamus determines whether LH or FSH is secreted from the anterior pituitary.

Question 35

A male with 5 alpha-reductase deficiency will have male internal sex organs but more female appearing external genitals.

Question 36

A lack of testosterone in males will cause the genital tubercle to form a(n)

A)penis.
B)testis.
C)clitoris.
D)ovary.

Question 37

Synthetic analogues of GnRH are useful in treating benign prostatic hyperplasia and endometriosis.

Question 38

The gonads have a negative feedback effect on gonadotropins of the anterior pituitary.

Question 39

The embryonic urethral fold becomes the female

A)labia minorA.
B)labia majora.
C)glans clitoris.
D)All of these choices are correct.

Question 40

Epiphyseal growth in males is stimulated by estrogen.

Question 41

Male androgens

A)stimulate protein synthesis and muscle growth.
B)stimulate bone growth.
C)stimulate erythropoiesis.
D)All of the choices are correct.

Question 42

The correct order of the four phases of sexual response in both sexes would be

A)excitation,plateau,orgasm,resolution.
B)plateau,excitation,orgasm,resolution.
C)orgasm,excitation,resolution,plateau.
D)resolution,plateau,excitation,orgasm.

Question 43

The majority of the testis is comprised of

A)Leydig cells.
B)interstitial cells.
C)Sertoli cells.
D)seminiferous tubules.

Question 44

Estrogen may play a role in spermatogenesis as evidenced by estrogen receptors found on developing

A)sperm cells.
B)brains.
C)uterine.
D)oocytes.

Question 45

Damage to the Sertoli cells would result in the production of antibodies against sperm cells.

Question 46

Which of the following is a precursor to melatonin synthesis?

A)tryptophan
B)serotonin
C)tyrosine
D)Both tryptophan and serotonin are correct.

Question 47

The role of melatonin in puberty of humans is well established and critical.

Question 48

Sertoli cells are stimulated by __________,while Leydig cells are stimulated by ________.

A)FSH,LH
B)LH,FSH
C)testosterone,LH
D)FSH,testosterone

Question 49

The Leydig cells of the testes constitute a blood-testis barrier that prevents autoimmune destruction of the sperm.

Question 50

In males,the levels of testosterone decline drastically with age.

Question 51

In males androgens are required for

A)initiation of spermatogenesis at puberty.
B)regression of the wolffian ducts during embryonic development.
C)maintenance of accessory sex organs.
D)development of the Müllerian ducts.

Question 52

What enzyme is needed for the conversion of testosterone into estradiol in the male brain?

A)5-alpha reductase
B)aromatase
C)ATPase
D)cGMP phosphodiesterase

Question 53

Women who are very lean and physically active may have irregular cycles and amenorrhea.

Question 54

Women do not enter a refractory period following orgasm and are capable of multiple orgasms.

Question 55

Pubic and axillary hair growth at puberty is from increased secretion of

A)anterior pituitary gonadotropins.
B)estrogen and testosterone from the onads.
C)androgens from the adrenal cortex.
D)melatonin from the pineal glanD.

Question 56

Secretion of LH is inhibited by

A)high concentrations of inhibin.
B)rapidly rising concentrations of estradiol.
C)high concentrations of testosterone.
D)decreasing concentrations of progesterone.

Question 57

Longitudinal growth during development is dependent on estrogen stimulation of the epiphyseal growth plates in both males and females.

Question 58

In males,conversion of testosterone to estrogen in the brain is essential for normal regulation of LH secretion.

Question 59

Developing sperm cells produce estrogen that may serve to regulate their environment.

Question 60

Secretions of the Sertoli cells and cells of Leydig influence the functions of each other.

Question 61

Removal of the ___________ would result in a lack of energy in the semen to support the sperm cells.

A)seminal vesicles
B)prostate
C)testis
D)epididymis

Question 62

The movement of semen into the urethra is called

A)emission.
B)erection.
C)ejaculation.
D)ovulation.

Question 63

The most successful method of contraception is

A)vasectomy.
B)oral contraceptives.
C)the rhythm method.
D)condom usage.

Question 64

Sperm are stored and matured in the

A)vas deferens.
B)seminal vesicles.
C)epididymis.
D)prostate glanD.

Question 65

After meiosis I in males,________ are formed.

A)primary spermatocytes
B)secondary spermatocytes
C)spermatids
D)spermatozoa

Question 66

The myometrium is the inner most layer of the uterus.

Question 67

Nitric oxide released by endothelial cells in vascular smooth muscle is responsible for smooth muscle relaxation and therefore responsible for which of the following?

A)reduced blood flow to bronchioles
B)increased blood flow in placenta
C)increased blood flow to the fetus
D)penile erection

Question 68

Which of the following is NOT a function of Sertoli cells?

A)production of androgen-binding protein
B)FSH stimulation of spermiogenesis
C)protection of developing sperm from the male's immune system
D)production of testosterone

Question 69

About 60% of the volume of semen is produced by the

A)seminal vesicles.
B)prostate gland.
C)bulbourethral glands.
D)testes.

Question 70

Viagra works by blocking ________________ in order to raise cGMP concentration and promote vasodilation of vascular smooth muscle of the penis to produce an erection.

A)5-alpha reductase
B)aromatase
C)ATPase
D)cGMP phosphodiesterase

Question 71

How many sperm are produced from one spermatogonium?

A)one
B)two
C)four
D)eight

Question 72

Apoptosis of T lymphocytes requires that Sertoli cells produce

A)FAS ligand.
B)androgen-binding protein.
C)testosterone.
D)All of these choices are correct.

Question 73

Emission and ejaculation are under parasympathetic nerve control.

Question 74

FSH is necessary for spermiogenesis to occur.

Question 75

Spermatogenesis is regulated by

A)FSH.
B)testosterone and its derivatives.
C)growth hormone.
D)progesterone.

Question 76

Tight junctions between ___________ are responsible for the formation of the blood-testis barrier.

A)Leydig cells
B)Sertoli cells
C)spermatogonial cells
D)trophoblast cells

Question 77

What occurs during spermiogenesis?

A)chromosomes are compacted by protamines
B)flagellum and acrosome form
C)cytoplasm removed by Sertoli cells
D)All of the choices are correct.

Question 78

What allows the compaction of chromatin in the process of spermiogenesis?

A)histones
B)acrosome
C)protamines
D)testosterone

Question 79

Male contraceptive drugs that would block FSH would be very effective for birth control.

Question 80

In the female menstrual cycle

A)ovulation is stimulated by decreasing concentrations of progesterone.
B)menstruation occurs during the last four days of the cycle.
C)progesterone secretion is stimulated by LH.
D)the luteal phase is characterized by high circulating concentrations of estrogens.