Repro - Physiology

Question 1

How long does it take for the development of a mature spermatid?

Answer 1

2 months

Question 2

Where does spermatogenesis occur in the testis?

Answer 2

In the seminiferous tubules

Question 3

Put the following in order of their development during spermatogenesis: spermatozoan, primary spermatocyte, secondary spermatocyte, spermatid, and spermatogonium.

Answer 3

Spermatogonium, primary spermatocyte, secondary spermatocyte, spermatid then spermatozoan

Question 4

In spermatogenesis, what is the immature form of sperm called? What is the mature form called?

Answer 4

Spermatogonium; spermatozoan (remember: Gonium is going to be a sperm; Zoan is Zooming out of testis)

Question 5

A spermatogonium has _____ (number) _____ (single chromosomes/sister chromatids), is _____ (diploid/haploid), and is _____ (4N/2N/N).

Answer 5

46; single chromosomes; diploid; 2N

Question 6

A primary spermatocyte has _____ (number) _____ (single chromosomes/sister chromatids), is _____ (diploid/haploid), and is _____ (4N/2N/N).

Answer 6

46; sister chromatids; diploid; 4N

Question 7

A secondary spermatocyte has _____ (number) _____ (single chromosomes/sister chromatids), is _____ (diploid/haploid), and is _____ (4N/2N/N).

Answer 7

23; sister chromatids; haploid; 2N

Question 8

A spermatid has _____ (number) _____ (single chromosomes/sister chromatids), is _____ (diploid/haploid), and is _____ (4N/2N/N).

Answer 8

23; single chromosomes; haploid; N

Question 9

What events define the process known as spermiogenesis?

Answer 9

The spermatid becomes a spermatozoan by losing cytoplasmic contents and gaining an acrosomal cap

Question 10

During spermatogenesis, _____ undergoes meiosis I to form _____, whereas _____ undergoes meiosis II to form _____.

Answer 10

Primary spermatocyte; secondary spermatocyte; sperm

Question 11

In males, follicle-stimulating hormone stimulates which cells? What is the resulting secretion?

Answer 11

Follicle-stimulating hormone stimulates Sertoli cells to produce androgen-binding protein and inhibin

Question 12

In males, luteinizing hormone stimulates which cells? What is the resulting secretion?

Answer 12

Luteinizing hormone stimulates Leydig cells to produce testosterone

Question 13

In male spermatogenesis, what is the effect of inhibin released by Sertoli cells?

Answer 13

Inhibin provides negative feedback of follicle-stimulating hormone release by the anterior pituitary

Question 14

How does testosterone affect the hypothalamus-pituitary axis in the regulation of spermatogenesis?

Answer 14

Testosterone is necessary for sperm production in the testes but provides negative feedback on gonadotropin-releasing hormone and luteinizing hormone secretion in the hypothalamus and pituitary

Question 15

Gonadotropin-releasing hormone from the hypothalamus stimulates the release of what two hormones from the anterior pituitary?

Answer 15

Luteinizing hormone and follicle-stimulating hormone

Question 16

What are the functions of luteinizing hormone and follicle-stimulating hormone?

Answer 16

Follicle-stimulating hormone causes Sertoli cells to aid in Sperm production, whereas LH causes Leydig cells to release testosterone (also aiding sperm production)

Question 17

Rank the following three androgens in order of potency: androstenedione, dihydrotestosterone, and testosterone.

Answer 17

Dihydrotestosterone > testosterone > androstenedione

Question 18

What is the major source of dihydrotestosterone and testosterone in men?

Answer 18

The testis

Question 19

What is the major source of androstenedione in men?

Answer 19

The adrenals

Question 20

What enzyme converts testosterone to dihydrotestosterone?

Answer 20

5α-Reductase

Question 21

What medication inhibits 5α-reductase?

Answer 21

Finasteride

Question 22

What enzyme converts testosterone and dihydrotestosterone to estrogen in men? Where is this enzyme found?

Answer 22

Aromatase, which is found in adipose tissue and Sertoli cells

Question 23

What effects does testosterone have during puberty?

Answer 23

Testosterone is responsible for the growth spurt (affecting the penis, seminal vesicles, sperm, muscle, and red blood cell development), deepening of the voice, increased libido, and closure of epiphyseal plates (ending linear growth)

Question 24

Name three structures in which differentiation depends on testosterone during embryogenesis.

Answer 24

The epididymis, the vas deferens, and the seminal vesicles

Question 25

How does testosterone cause epiphyseal plate closure in men?

Answer 25

Testosterone is converted to estrogen, which closes epiphyseal plates

Question 26

What are the effects of dihydrotestosterone during male embryogenesis?

Answer 26

Differentiation of the penis, scrotum, and prostate

Question 27

What are the effects of dihydrotestosterone on adult males?

Answer 27

Balding, prostate growth, and sebaceous gland activity

Question 28

A bodybuilder comes to your office for infertility, and on exam you note small testicles; what is a likely cause of his infertility?

Answer 28

Azoospermia, caused by exogenous testosterone use resulting in hypothalamic-pituitary-gonadal axis inhibition and low intratesticular testosterone

Question 29

Name four places in female body where estrogen is produced.

Answer 29

The ovaries (17β-estradiol), the placenta (estriol), the blood (aromatization), and the adipose tissue

Question 30

Rank the following three forms of estrogen in order of potency: estradiol, estriol, and estrone.

Answer 30

Estradiol > estrone > estriol

Question 31

What major hormone is produced by the granulosa cells?

Answer 31

Estrogen via conversion of androstenedione by aromatase

Question 32

What major hormone is produced by the theca cells?

Answer 32

Androstenedione

Question 33

What is the effect of follicle-stimulating hormone in granulosa cells?

Answer 33

Follicle-stimulating hormone promotes the conversion of androstenedione to estrogen via the aromatase enzyme

Question 34

What is the effect of luteinizing hormone in theca cells?

Answer 34

Luteinizing hormone promotes the conversion of cholesterol to androstenedione via the enzyme desmolase

Question 35

What effects does estrogen have on the uterus and ovaries?

Answer 35

Estrogen stimulates follicle growth and endometrial proliferation and increases myometrial excitability

Question 36

What is the role of estrogen on physical development during puberty?

Answer 36

Genital and breast development and creation of female fat distribution

Question 37

What is the effect of estrogen on the liver?

Answer 37

Increased synthesis of binding globulins and transport proteins

Question 38

What is the effect of estrogen on the plasma lipid profile?

Answer 38

Increased high-density lipoprotein, decreased low-density lipoprotein

Question 39

How does estrogen affect follicle-stimulating hormone and luteinizing hormone levels?

Answer 39

It provides negative feedback on follicle-stimulating hormone and luteinizing hormone secretion except near ovulation, when estrogen provides positive feedback for the luteinizing hormone surge

Question 40

During pregnancy, what happens to the levels of endogenous estrogens?

Answer 40

There is a 50-fold increase in estradiol and estrone, and a 1000-fold increase in estriol

Question 41

Which is an indicator of fetal well being during pregnancy, an increase in estradiol or estriol?

Answer 41

Estriol

Question 42

What is the effect of estrogen on prolactin levels and function?

Answer 42

Estrogen increases prolactin secretion butblocks the action of prolactin at the breast

Question 43

Name four places in the human body where progesterone is produced.

Answer 43

Corpus luteum, placenta, adrenal cortex, and testes

Question 44

Progesterone causes what changes in the endometrium?

Answer 44

Spiral artery development and increased glandular secretions

Question 45

What effect does progesterone have on pregnancy?

Answer 45

Progesterone maintains the pregnancy (remember: PROGESTerone is PRO-GESTation)

Question 46

Progesterone _____ (increases/decreases) myometrial contractility whereas estrogen _____ (increases/decreases) myometrial contractility.

Answer 46

Decreases, increases

Question 47

What is the effect of progesterone on cervical mucus?

Answer 47

Progesterone thickens cervical mucus to prevent sperm entry

Question 48

Progesterone causes what effect on body temperature?

Answer 48

Increases body temperature; basal body temperature can be used to predict ovulation

Question 49

What is the effect of progesterone on uterine smooth muscle?

Answer 49

It causes decreased myometrial contractility and smooth muscle relaxation

Question 50

Progesterone levels are monitored daily during a woman's menstrual cycle; what conclusion can you make upon noting an elevation in the progesterone level?

Answer 50

Progesterone elevation indicates that ovulation has occurred

Question 51

What hormone stimulates endometrial proliferation during the menstrual cycle?

Answer 51

Estrogen

Question 52

What hormone maintains endometrium to support implantation?

Answer 52

Progesterone; fertility is decreased without progesterone

Question 53

When do luteinizing hormone levels peak during the menstrual cycle?

Answer 53

Luteinizing hormone levels peak just before ovulation

Question 54

How long does the luteal phase of the menstrual cycle typically last?

Answer 54

14 days; therefore, ovulation day + 14 days = menstruation

Question 55

How long does the follicular phase of the menstrual cycle typically last?

Answer 55

The follicular phase can vary in length, and this variation is what alters the length of the menstrual cycle

Question 56

Estrogen levels peak _____ (after/before) ovulation, whereas progesterone levels peak _____ (after/before) ovulation.

Answer 56

Before; after

Question 57

Does the graafian follicle mature during the follicular or luteal phase?

Answer 57

Follicular phase

Question 58

Is the corpus luteum present during the follicular or luteal phase?

Answer 58

Luteal phase; the corpus luteum is formed from the ruptured follicle

Question 59

Regression of the corpus luteum leads to what event?

Answer 59

Menstruation; when progesterone levels decrease the endometrial lining sloughs off

Question 60

Put these events of the menstrual cycle in order: progesterone release from the corpus luteum, increase in luteinizing hormone secretion, menstruation, ovulation and increase in estrogen secretion.

Answer 60

Increase in estrogen secretion, increase in luteinizing hormone secretion, ovulation, progesterone release from the corpus luteum and menstruation

Question 61

Oligomenorrhea is defined as a cycle lasting more than _____ days, whereas polymenorrhea is defined as a cycle lasting fewer than _____days.

Answer 61

35 days; 21 days

Question 62

What is the difference between metrorrhagia and menometrorrhagia?

Answer 62

Metrorrhagia is frequent and irregular menstruation (often called spotting), whereas menometrorrhagia is irregular, heavy menstruation

Question 63

A woman presents with pain in her right lower quadrant on the fourteenth day of her menstrual cycle, which is normally 28 days. After ruling out appendicitis, you determine this is caused by blood from a ruptured ovarian follicle at ovulation, also known as what?

Answer 63

Mittelschmerz; the blood from the ruptured follicle may cause peritoneal irritation that can mimic appendicitis

Question 64

What happens following the luteinizing hormone surge in the normal menstrual cycle?

Answer 64

Luteinizing hormone surge stimulates the rupture of the follicle and ovulation

Question 65

When does a primary oocyte undergo and complete meiosis I?

Answer 65

Meiosis I begins during fetal life and is completed just before ovulation

Question 66

In what stage of meiosis I is an oocyte arrested in between fetal life and ovulation?

Answer 66

Prophase (remember that meiosis I is in prOphase until Ovulation)

Question 67

In what stage of meiosis II is a secondary oocyte arrested in between ovulation and fertilization?

Answer 67

METaphase (remember that an egg MET a sperm)

Question 68

An oogonium is _____ (diploid/haploid) , _____ (2N/4N) and contains _____ (23/46) _____ (single chromosomes/sister chromatids/single chromatids).

Answer 68

Diploid; 2N; 46; single chromosomes

Question 69

A primary oocyte is _____ (diploid/haploid), _____ (2N/4N) and contains _____ (23/46) _____ (single chromosomes/sister chromatids/single chromatids).

Answer 69

Diploid; 4N; 46; sister chromatids

Question 70

A secondary oocyte is _____ (diploid/haploid), _____ (2N/4N) and contains _____ (23/46) _____ (single chromosomes/sister chromatids/single chromatids).

Answer 70

Haploid; 2N; 23; sister chromatids

Question 71

An ovum is _____ (diploid/haploid), _____ (N/2N) and contains _____ (23/46) _____ (single chromosomes/sister chromatids/single chromatids).

Answer 71

Haploid; N; 23; single chromatids

Question 72

What stage of oogenesis begins with an oogonium and ends with a primary oocyte?

Answer 72

Replication (interphase)

Question 73

What stage of oogenesis begins with a primary oocyte and ends with a secondary oocyte and a polar body?

Answer 73

Meiosis I

Question 74

What stage of oogenesis begins with a secondary oocyte and ends with an ovum and a polar body?

Answer 74

Meiosis II

Question 75

Where does fertilization most commonly occur?

Answer 75

In the upper end of the oviduct (the ampulla)

Question 76

When does fertilization occur in relation to ovulation?

Answer 76

Fertilization commonly occurs within one day of ovulation

Question 77

When does implantation occur in relation to fertilization?

Answer 77

Implantation occurs 6 days after fertilization

Question 78

When is β-human chorionic gonadotropin first detectable in the blood after conception? In the urine?

Answer 78

β-Human chorionic gonadotropin can first be detected in the blood 1 week after conception, and in the urine 2 weeks after conception

Question 79

What is the source of β-human chorionic gonadotropin shortly following conception?

Answer 79

β-Human chorionic gonadotropin is secreted by trophoblasts

Question 80

In which trimester does the β-human chorionic gonadotropin level peak?

Answer 80

In the first trimester; after the first trimester, the placenta becomes the source of progesterone so high β-human chorionic gonadotropin levels are not needed to maintain the corpus luteum

Question 81

In pregnancy when do progesterone, estriol, and prolactin levels peak?

Answer 81

The levels increase throughout pregnancy

Question 82

What process induces lactation? When does this occur?

Answer 82

The decrease in maternal hormones (estrogen) induces lactation after labor (recall that estrogen blocks the action of prolactin at the breasts)

Question 83

Why is suckling necessary to maintain milk production?

Answer 83

Suckling stimulates nerves that induce increased oxytocin and prolactin levels

Question 84

What are two roles of prolactin in the perinatal period?

Answer 84

Prolactin induces and maintains milk production and decreases reproductive function

Question 85

What are two functions of oxytocin in the perinatal period?

Answer 85

Oxytocin increases milk letdown and is involved with uterine contractions

Question 86

A woman has abnormally elevated human chorionic gonadotropin levels for her gestational age and you suspect gestational trophoblastic disease; name three examples of this disease.

Answer 86

Hydatidiform moles, choriocarcinoma, and gestational trophoblastic tumors

Question 87

A woman presents to your office having missed her period 2 weeks ago; what noninvasive test can you perform to determine if she is pregnant?

Answer 87

A urinary human chorionic gonadotropin test can be used to detect early pregnancy

Question 88

What is the role of human chorionic gonadotropin in the first trimester of pregnancy?

Answer 88

By acting like luteinizing hormone, human chorionic gonadotropin maintains the corpus luteum, which is the source of progesterone

Question 89

During the second and third trimesters, where are human chorionic gonadotropin, estriol and progesterone produced?

Answer 89

The placenta

Question 90

What physiologic process occurs as the number of ovarian follicles decrease with age?

Answer 90

The cessation of estrogen production resulting in menopause

Question 91

What happens to levels of estrogen, luteinizing hormone, follicle-stimulating hormone, and gonadotropin-releasing hormone during menopause?

Answer 91

Estrogen decreases, whereas luteinizing hormone, follicle-stimulating hormone, and gonadotropin-releasing hormone increase

Question 92

After 4-5 years of abnormal menstrual cycles, a 50 year-old woman presents with amenorrhea, pain during intercourse, and feelings of heat in her chest; what test would confirm the most likely diagnosis?

Answer 92

This is likely menopause, with amenorrhea, vaginal atrophy causing dyspareunia, and hot flashes; a serum follicle-stimulating hormone level will be greatly elevated

Question 93

What is the average age for the onset of menopause in nonsmokers?

Answer 93

51 years; menopause occurs earlier in smokers

Question 94

What is the main source of estrogen following menopause?

Answer 94

The peripheral conversion of androgens into estrogen; increased androgens may cause hirsutism

Question 95

A 35-year-old woman presents with amenorrhea, hot flashes, and a low bone mineral density; what diagnosis is likely?

Answer 95

She has symptoms of early menopause, which may indicate premature ovarian failure

Question 96

What are the clinical and pathologic manifestations of menopause?

Answer 96

Hirsutism, Hot flashes, Atrophy of the Vagina, Osteoporosis, Coronary artery disease (remember: menopause causes HHAVOC)