Reproductive Physiology (Module 9)

Question 1

Gonads are indifferent or bipotential during this gestational life?

A. First 5 weeks of gestation
B. First 6 weeks of gestation
C. First 7 weeks of gestation
D. First 9 weeks of gestation

Answer 1

Answer: A

During weeks 6 and 7 in genetic males, the testes begin t develop while during week 9 in genetic females, ovaries begin to develop. During the first 5 weeks of gestation, this is where the gonads are indifferent or bipotential, they are neither male nor female.

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 447

Question 2

Which of the following statements are true?

A. Sertoli cells synthesize antimullerian hormone; Theca Cells synthesize Testosterone
B. Sertoli cells synthesize Progesterone; Granulosa cells synthesize estradiol
C. Leydig Cells synthesize Testosterone; Theca cells synthesize Progesterone
D. None of the above

Answer 2

Answer: C

In the male gonads, Sertoli cells synthesize a glycoprotein called antimullerian hormone and Leydig cells synthesize testosterone.
In the female gonads, Theca cells synthesize progesterone and Granulosa cells synthesize estradiol

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 447

Question 3

Responsible for fetal differentiation of the external male genitalia?

A. Finasterine
B. Testosterone
C. Dihydrotestosterone
D. 5 Alpha Reductase Inhibitor

Answer 3

Answer: C

Finasterine ia an example of a 5 Alpha Reductase Inhibitor in which blocks the conversion of testosterone to dihydrotestosterone.
Testosterone is responsible for the fetal differentiation of the internal male genitalia and Dihydrotestosterone is responsible for the external male genitalia

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 455

Question 4

Which of the following statements are true about the important functions of the sertoli cells?

A. The Sertoli cells provide nutrients to the differentiating sperm which are not isolated from the bloodstream
B. Sertoli cells form gap junctions with each other creating a barrier called blood-testes barrier
C. Sertoli cells secrete an aqueous fluid that helps to transport sperm
D. All of the above

Answer 4

Answer: C

Sertoli cells provide nutrients into differentiating sperm
which are isolated from the bloodstream. It is tight junctions not gap junctions that creates the barrier called blood-testes barrier.

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 452

Question 5

A one full cycle of spermatogenesis requires:

A. 46 days
B. 32 days
C. 64 days
D. 14 days

Answer 5

Answer: C

One full cycle of spermatogenesis requires about 64 days.

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 452

Question 6

Which of the following are not mediated by Testosterone?

A. Libido
B. Spermatogenesis
C. Male hair pattern
D. None of the above

Answer 6

Answer: C

Male hair pattern is mediated by Dihydrotestosterone

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 456

Question 7

Development of adults breast is absoluteky dependent on:

A. Oxytocin
B. Estrogen
C. Prolactin
D. None of above

Answer 7

Answer: B

Oxytocin is responsible for milk ejection.
Prolactin is responsible for milk production.
Development of breast is absolutely dependent on estrogen.

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 461

Question 8

Which of the following statements in menopause is true?

A. Number of functional ovarian follicles increases
B. Estrogen secretion is increased
C. FSH and LH secretion increased
D. All of the above

Answer 8

Answer: C

During menopause, number of functional ovarian follicles are decreased.
Estrogen secretion declines. FSH and LH are increased.

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 467

Question 9

True or False: Puberty is initiated by the pulsatile secretion of GnRH?

A. True
B. False

Answer 9

Answer: A

Puberty in male and females are initiated by the pulsatile secretion of
GnRH which drives the secretion of FSH and LH which drives the
testes and ovaries to secrete their respective sex steroid hormone

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 467

Question 10

Which of the following statements are true?

A. During ovulation, there is a decrease in 17 beta estradiol
B. During Follicular Phase, there is an increase basal body temperature and increase in 17 beta estradiol.
C. During Luteal Phase, there is an increase in progesterone, increase in basal body temperature.
D. All of the statements are true

Answer 10

Answer: C

During Follicular Phase, there is a decrease in basal body temperature, increase in 17 beta estradiol. During ovulation FSH and LH surge marks the ovulation period and basal body temperature starts to increase also there is a decrease in 17 beta estradiol.

Reference: Costanzo, L. (2014). Physiology Fifth Edition. Page 463

Question 11

Important points regarding capacitation of spermatozoa include/s:

A. The haploid number of chromosomes of the egg
B. The membrane of the sperm becomes permeable to calcium ions
C. Sperm cells gradually lose their inhibitory cholesterol
D. Both B and C

Answer 11

Answer: D

Cholesterol is added to the cell membrane covering the acrosome
of the sperm while in the male genital duct, which toughens it and preventing release of enzymes; however, entering the female genital tract removes these cholesterol over the next few hours, making the acrosome weaker. The membrane of the sperm also becomes more permeable to calcium ions in the female genital tract, allowing it to be much more motile.

Reference: Guyton and Hall Medical Physiology, 13th ed, p.977

Question 12

These are all functions of testosterone in a male human body EXCEPT:

A. Deepening of the voice
B. Increase in basal metabolic rate
C. Increase in skin thickness and can contribute to acne
D. Positive feedback to the anterior pituitary to secrete more LH and FSH

Answer 12

Answer: D

“Testosterone secreted by the testes in response
to LH has the reciprocal effect of inhibiting anterior
pituitary secretion of LH … which probably results
from a direct effect of testosterone on the
hypothalamus to decrease the secretion of GnRH.”

Reference: Guyton and Hall Medical Physiology, 13th ed, p.979

Question 13

Penile erection is caused mainly by

A. Nitric oxide released by sympathetic nerves
B. Nitric oxidase released by parasympathetic nerves
C. Nitric oxide released by parasympathetic nerves
D. Vasoactive intestinal peptide released by sympathetic nerves

Answer 13

Answer: C

Penile erection is caused by parasympathetic nerves,
which release nitric oxide and/or vasoactive intestinal
peptide with acetylcholine.

Reference: Guyton and Hall Medical Physiology, 13th ed, p.979

Question 14

A male patient was diagnosed with Klinefelter’s Syndrome (XXY chromosome). Which of the following would be manifested on this patient?

A. Normal development of the male reproductive tract
B. Gynecomastia (development of male breasts)
C. Increased libido
D. High levels of testosterone

Answer 14

Answer: B

Klinefelter’s Syndrome, a condition of primary hypogonadism, involves the abnormal development of the testes, specifically in the Leydig and Sertoli cells. Secondary sex characteristics do not appear, with accompanied gynecomastia.

Reference: Vander’s Human Physiology The Mechanisms of Body Function, 13th ed., p. 620

Question 15

Both hormones are produced and secreted by the corpus luteum during the luteal phase, and these are:

A. Progesterone and estrogen
B. Progesterone and LH
C. Estrogen and LH
D. Human Chorionic Gonadotropin (HCG) and Progesterone

Answer 15

Answer: A

The granulosa cells in the corpus luteum develop extensive intracellular smooth endoplasmic reticula that form large amounts of the female sex hormone progesterone and estrogen (more progesterone than estrogen during the luteal phase).

Reference: Guyton and Hall Medical Physiology, 13th ed, p.991

Question 16

Which of the following is a function of the circulating estrogen in a pregnant woman?

A. Decidual cells develop in the uterine endometrium
B. Prevents involution of the corpus luteum
C. Enlargement of the mother’s uterus, breasts, ductal structure, and external genitalia
D. Decreases the contractility of the uterus

Answer 16

Answer: C

Choices A and D are functions of the progesterone, while choice B is a function by HCG.

Reference: Guyton and Hall Medical Physiology, 13th ed, p.1008

Question 17

Which of the following statements is/are true?

A. B-estradiol has a stronger effect than estrone and estriol
B. Estrone has a stronger effect than B-estradiol and estriol
C. Estriol has a stronger effect than B-estradiol and estrone
D. Estrone has a weaker effect than B-estradiol and estriol

Answer 17

Answer: A

“The estrogenic potency of B-estradiol is 12 times that of estrone and 80 times that of estriol.”

Reference: Guyton and Hall Medical Physiology, 13th ed, p.992

Question 18

A pregnant woman who is three weeks away from her due date was brought to the hospital and was diagnosed with preeclampsia. Which of the following would be expected?

A. Hyponatremia and decreased water retention by the mother’s kidneys
B. Insufficient blood supply to the placenta
C. Decreased blood pressure
D. Increased blood flow to the kidneys

Answer 18

Answer: D

“Insufficient blood flow to the placenta causes it to release various substances that enter the mother’s circulation and cause impaired vascular endothelial function, decreased blood flow to the kidneys, excess salt and water retention, and increased blood pressure.”

Reference: Guyton and Hall Medical Physiology, 13th ed, p.1011

Question 19

A woman was diagnosed with endometriosis. Which of the following is expected?

A. Female infertility due to anovulation
B. Female infertility due to fibrosis throughout the pelvis
C. Female infertility due to inflammation of the fallopian tubes
D. Female infertility due to abnormal hormonal stimulation

Answer 19

Answer: B

“Endometriosis causes fibrosis throughout the pelvis, and this fibrosis sometimes so enshrouds the ovaries that an ovum cannot be released into the abdominal cavity. Often, endometriosis occludes the fallopian tubes, either at the fimbriated ends or elsewhere along their extent.”

Reference: Guyton and Hall Medical Physiology, 13th ed, p.1001

Question 20

This occurs as a result of the estrogen-induced Lutenizing Hormone surge

A. Menses
B. Follicular Phase
C. Luteal Phase
D. Ovulation

Answer 20

Answer: B

A burst of estradiol synthesis at the end of the follicular phase has a positive feedback effect on the secretion of FSH and LH surge

Reference: BRS Physiology, 5th ed. p. 254

Question 21

Female: Negative and positive feedback control

A. Progesterone
B. Estrogen
C. Both A and B
D. None of the above

Answer 21

Answer: C

Estrogen has both negative and positive feedback effects on FSH and LH secretion; progesterone has negative feedback effects on FSH and LH secretion durin luteal phase

Reference: BRS Physiology, 5th ed. p. 253

Question 22

FSH acts on the Sertoli cells to maintain _______

A. testosterone synthesis
B. LH secretion
C. spermatogenesis
D. FSH secretion

Answer 22

Answer: C

FSH acts on the Sertoli cells to maintain spermatogenesis, the Sertoli cells also secrete inhibin, which involved in negative feedback of FSH secretion

Reference: BRS Physiology, 5th ed. p.251

Question 23

Inhibits the secretion of LH

A. Inhibin
B. Testosterone
C. Dihydrotestosterone
D. Androgen

Answer 23

Answer: B

Testosterone inhibits the secretion of LH by inhibiting the release of GnRH from the hypothalamus and by directly inhibitin the release of LH from the anterior pituitary

Reference: BRS Physiology, 5th ed. p.251

Question 24

Function of testosterone

A. Male pattern baldness
B. Decreases protein formation and muscle development
C. Loss of body hair
D. Decreases Basal Metabolic Rate

Answer 24

Answer: A

Testosterone decreases the growth of hair on top of the head

Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p. 1030

Question 25

Normal sperm count A. 15M-100M/mL B. 35M-200M/mL C. 10M-150M/mL D. 3M-100M/mL

Answer 25

Answer: B Normal sperm count is 35M-200M/mL Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p. 1026

Question 26

Contraction of the vas deferens and the ampulla to cause expulsion of sperm into the internal urethra A. Ejaculation B. Penile Erection C. Lubrication D. Emission

Answer 26

Answer: D Emission begins with contration of the vas deferns and the ampulla to cause expulsion of sperm into the internal urethra Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. P.1027

Question 27

Caused by parasympathetic impulses that pass from the sacral portion of the spinal cord through the pelvic nerves to the penis A. Ejaculation B. Penile Erection C. Lubrication D. Emission

Answer 27

Answer: B Penile erection is caused by parasympathetic impulses that pass from the sacral portion of the spinal cord through the pelvic nerves to the penis Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1027

Question 28

Parasympathetic nerve fibers release Nitric Oxide, which activates the enzyme A. cGMP B.guanylyl monophosphate C. nitric oxide D. vasoactive intestinal peptide

Answer 28

Answer: B Parasympathetic nerve fibers release Nitric Oxide, which activates the enzyme guanylyl cyclase, causing increased formation of cGMP Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1027

Question 29

Relaxes the arteries of the penis and the trabecular meshwork of smooth muscle fibers A. cGMP B.guanylyl monophosphate C. nitric oxide D. vasoactive intestinal peptide

Answer 29

Answer: A cGMP especially relaxes the arteries of the penis and the trabecular meshwork of smooth muscle fibers in the erectile tissue of the corpora cavernosa and corpus sponiosum in the shaft of the penis Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. P.1027

Question 30

Release of sperm or __________, is controlled by Sertoli cells. A. Sperm Migration B. Spermiation C. Sperm Evolution D. Spermifusion

Answer 30

Answer: B The release of sperm or spermiation is controlled by Sertoli cells Reference: Berne & Levy Physiology 6th ed P. 1292

Question 31

What is the specialized, immunologically safe microenvironment for the developing sperm? A. Encapsulation B. Scrotum C. Blood-testis barrier D. Colostrum

Answer 31

Answer: C By blocking paracellular diffusion, the tight junctions restrict movement of substances between blood and the developing germ cells through a trans-Sertoli transport pathway and, in this manner allow the Sertoli cell to control the availability of nutrients to the germ cells Reference: Berne & Levy Physiology 6th ed P 1.294

Question 32

What induces the regression of the embryonic mullerian duct? A. Androgen-binding protein B. Leydig Cell C. Bartholin's cell D. Mullerian Inhibitory substance

Answer 32

Answer: D Antimullerian hormone = Mullerian Inhibitory substance, induces regression of the emryonic mullerian duct that is programmed togive rise to the female reproductive tract Reference: Berne & Levy Physiology 6th ed P 1.294

Question 33

Spermatozoa also undergo this process, which involves changes in the cell membrane to prevent spermatozoa from undergoing the acrosome reaction before the contact with an egg. A. Capacitation B. Decapacitation C. Activation D. Maturation

Answer 33

Answer: B Spermatozoa also undergo the process of Decapacitation, which involves changes in the cell membrane to prevent spermatozoa from undergoing the acrosome reaction before the contact with an egg. Reference: Berne & Levy Physiology 6th ed P. 1300

Question 34

A major development in the treatment of some forms of Erectile Dysfunction is the use of these types of drugs which assist in the maintainance of an erection. A. Cox-2-selective inhibitors B. Calcium Channel blockers C. ACE-inhibitors D. cGMP Phosphodiesterase inhibitors

Answer 34

Answer: D Increased levels of cGMP in the corpus cavernosum, resulting in smooth muscle relaxation and inflow of blood to the corpus cavernosum Reference: Berne & Levy Physiology 6th ed P. 1301

Question 35

What is the proper term for irregular and sometimes prolonged menstrual flow between normal periods? A. Metrorrhagia B. Menorrhagia C. Oligomenorrhea D. Dysmenorrhea

Answer 35

Answer: A Metrorrhagia (irregular and sometimes prolonged menstrual flow in between normal periods) Reference: Berne & Levy Physiology 6th ed P. 1322

Question 36

The vaginal wall is innervated by branches of the ____________, which contribute to the sexual pleasure and orgasm during intercourse A. Vagus Nerve B. Abdomino-Pelvic Nerve C.Sciatic Nerve D. Pudendal Nerve

Answer 36

Answer: D The vaginal wall is innervated by branches of the Pudendal nerve, which contribute to sexual pleasure and orgasm during intercourse Reference: Berne & Levy Physioogy 6th ed P. 1323

Question 37

In pregnancy and mammalian egg activation, a _____ initial release of Ca++ is followed by a series of ______ Ca++ oscillations that can last for hours. A. small;small B. large;large C. large;small D.small;large

Answer 37

Answer: C In mamalian eggs, a large initial release of Ca++ is followed by a series of subsequent smaller Ca++ oscillations that can last for hours. A major consequence of this signaling pathway is that it "wakes up" the metabolically quiescent egg so it can resume meiosis and begin embryonic dev't, this process is called egg activation Reference: Berne & Levy Physiology 6th ed P. 1328

Question 38

Human placental Lactogen is also called ____________ A. Human chorionic somatommamotropin B. dehydrooepiandrosterone sulfate C. Placenta accreta D. Placental Estrogen Hormone

Answer 38

Answer: A HPL is a 191-amino acid protein hormone produced in the syncitiotrophoblast that is structurally similar to growth hormone Reference: Berne & Levy Physiology 6th ed P. 1336

Question 39

Prolactin also inhibits the release of GnRH, this also has been called "nature's contraceptive" what is the proper medical term for this phenomenon? A. Prolactin phase B. Lactation activation C. PRL D. Lactational ammenorhea

Answer 39

Answer: D PRL also inhibits the release of GnRH, and consequently nursing can be associated with Lactational ammenorhea (Fig. 43-39 Berne & Levy Physiology 6th ed. P. 1339) This effect of prolactin has been called "nature's contraceptive" and it may play a role in spacing out pregnancies. Reference: Berne & Levy Physiology 6th ed P. 1336

Question 40

This stimulates sertoli cells needed for spermiogenesis A .Luteinizing Hormone B. Anterior pituitary gland C. Follicle stimulating hormone D.Estrogens

Answer 40

Answer: A FSH secreted by anterior pituitary gland stimulates Sertoli Cells in order to convert spermatids to sperm (Spermiogenesis) Reference: Guyton and Hall Medical Physiology Twelfth Edition p. 1795

Question 41

Normal pH level of seminal fluid: A. 8.5 B. 7.0 C. 7.5 D.7.0

Answer 41

Answer: C In order for the semen to live longer it needs a pH level of 7.5(neutral or slightly alkaline). The components in the seminal plasma attempt to compensate for this hostile environment of the vagina which is very acidic. A very low level of pH can cause a rapid death of the sperm. Reference:

Question 42

The three estrogens present in the plasma of human female are the following except: A. Estriol B. Estrone C. β-estradiol D.Progestins

Answer 42

Answer: D The 3 estrogens present in the plasma of a human female are estriol, estrone and β-estradiol. The principal estrogen secreted by the ovaries is β-estradiol. Small amount of estrones are also secreted while estriol is the product derived between β-estradiol and estrones. Reference:

Question 43

The entire period of emission and ejaculation is called: A. Penile Erection B. Lubrication C. Orgasm D. Resolution

Answer 43

Answer: C Male Orgasm icludes emission and ejaculation. Emission begins with contraction of the vas deferens and ampulla to cause expulsion of sperm into internal urethra. While ejaculation is the wave-like and rhythmical contraction of urethra to expel semen to the external environment Reference:

Question 44

Which increases during luteal phase? A. Progesterone B. Estrogen C. Both D. Neither

Answer 44

Answer: C In the luteal phase, progesterone stimulates secretion by endometrial glands, and also promotes blood vessel growth. In the luteal phase following ovulation, estrogen and progesterone are secreted by the corpus luteum, which forms through the action of luteinizing hormone (LH). Reference: Guyton and Hall Medical Physiology Twelfth Edition p. 1828

Question 45

What is the role of hyaluronidase when it comes to ovum penetration? A. It digests proteins in the structural elements of tissue cells that still adhere in the ovum B. It depolymerizes the hyaluronic acid polymers in the cellular cement that holds the ovarian granulosa cells together C. It binds specifically with receptor proteins in the zona pellucida D.None of the Above

Answer 45

Answer: B Stored in large quantities in sperm are hyaluronidase and proteolytic enzymes which needed for the pentration of the ovum. Proteolytic enzymes digest proteins in the structural elements of tissue cells that still adhere in the ovum. While hyaluronidase depolymerizes the hyaluronic acid polymers in the cellular cement that holds the ovarian granulosa cells together. Reference: Guyton and Hall Medical Physiology Twelfth Edition p. 1797

Question 46

What happens during emission? A. Contraction of the capsule of the prostate gland B. Contraction of the seminal vesicles C .BOTH D. NEITHER

Answer 46

Answer: C Emission begins with contraction of the vas deferens and ampulla to cause expulsion of sperm into internal urethra. Then contraction of the capsule of the prostate gland followed by the contraction of the seminal vesicles expel prostatic and seminal fluid also into the urethra , forcing the sperm forward. Reference: Guyton and Hall Medical Physiology Twelfth Edition p. 1801

Question 47

A male child was born with undescended but otherwise normal testes. What would be the problem? A. Low levels of testosterone B. Preterm birth C. Both D. A only

Answer 47

Answer: C The testes usually descend into the scrotum during the last 2 to 3 months of gestation when the testes begin secreting reasonable quantities of testosterone. Therefore, testosterone, a very important hormone in reproductive development, stimulates for the descent of the testes. Reference: Guyton and Hall Medical Physiology Twelfth Edition p. 1805

Question 48

Erectile dysfunction is the inability of the man to maintain erection of sufficient rigidity for satisfactory sexual intercourse. This is usually treated with: A. Viagra B. Levitra C. Cialis D. All are correct

Answer 48

Answer: D Erectile dysfunction is usually caused by vascular diseases at the age of 40yrs old. This is usually treated with phosphodiesterase inhibitors such as sildenafil (viagra), vardenafil(Levitra), and tadalafil(Cialis). These drugs increases the cGMP (needed for the erection) by inhibiting the enzyme phosphodiesterase, which rapidly degrades cGMP. Thus, these drugs may enhance and prolong the effect of cGMP to cause erection. Reference: Guyton and Hall Medical Physiology Twelfth Edition p. 1813

Question 49

The following statements about menstruation are are correct except: A. During menstruation, tremendous numbers of leukocytes are released along with necrotic material and blood. B. Within 4-7 days after menstruation starts, the loss of blood ceases because endometrium begins to re-epithelialized. C. During normal menstruation, appx. 40 milliliters of blood are lost. The menstrual fluid is normally clotting. D. All are correct

Answer 49

Answer: C The menstrual fluid is not normally clotting because a fibrinolysin is released along with the necrotic endometrial material. During excessive bleeding, the quantity of fibrinolysin may not be sufficient to prevent clotting. The presence of clots during menstruation is often clinical evidence of uterine pathology. Reference: Guyton and Hall Medical Physiology Twelfth Edition p.1833

Question 50

Normal sperm count: A. 10 - 20 Million / mL B. 30 - 50 Million/ mL C. 5 - 20 Million/ mL D. 10 - 50 Million / mL

Answer 50

Answer: B Although some books still consider 20 million/ ml as a normal sperm count, a sperm count of less than 20 million / mL is already consider abnormal. Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1026

Question 51

Most potent estrogen hormone A. Estrone B. Andreostenedione C. Esdiol D. Estriol

Answer 51

Answer: C The total estrogenic effect of β-estradiol is usually many times that of the other two together. Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1043

Question 52

Responsible for the vasodilation in penile erection A. cGMP B. Histamine C. Angiotensin D. Carbon Dioxide

Answer 52

Answer: A Due to parasympathetic stimulation, release of Nitric oxied activates guanylyl cyclase for the production of cGMPP which relaxes the arteries of the penis Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1027

Question 53

Hormone which block the action of Prolactin in the breast A. Estrogen B. Testosterone C. FSH D. Androstenedione

Answer 53

Answer: A Estrogens initiate growth of the breasts and of the milk-producing apparatus. They are also responsible for the characteristic growth and external appearance of the mature female breast. However, they do not complete the job of converting the breasts into milk-producing organs Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1045

Question 54

When does oogenesis starts to take place? A. Puberty B. Childhood C. Infancy D. Fetal life

Answer 54

Answer: D As early as fetal life, oogenesis takes place and creates primary oocytes which arrests as Prophase I Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1037

Question 55

At what stage does the secondary oocyte aarest? A. Prophase I B. Telophase II C. Metaphase II D. Prophase II

Answer 55

Answer: C Secondary oocyte arrests at Metaphase II until fertilization occurs Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1038

Question 56

Initial changes at the onset of menopause includes a ________ in production of inhibin and _________ in production of pituitary FSH A. Increase; Increase B. Decrease; Increase C. Decrease; Decrease D. Increase; Decrease

Answer 56

Answer: B At the onset of menopause, inhibin production decreases and FSH production increases due to inhibin's negative feedback Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1051

Question 57

Cells in which the implanted embryo gets its nutrients for growth and development during the first weeks of implantation A. Trophoblast cells B. Granulosa cells C. Decidual cells D. Follicular cells

Answer 57

Answer: C As the trophoblast cells invade the decidua, digesting and imbibing it, the stored nutrients in the decidua are used by the embryo for growth and development. During the first week after implantation, this is the only means by which the embryo can obtain nutrients Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1057

Question 58

The secretion of this hormone can first be measured in the blood 8 to 9 days after ovulation, shortly after the blastocyst implants in the endometrium A. HCG B. Estrogen C. Progesterone D. Prolactin

Answer 58

Answer: A Coincidental with the development of the trophoblast cells from the early fertilized ovum, the hormone human chorionic gonadotropin is secreted by the syncytial trophoblast cells into the fluids of the mother. The secretion of this hormone can first be measured in the blood 8 to 9 days after ovulation, shortly after the blastocyst implants in the endometrium. Then the rate of secretion rises rapidly to reach a maximum at about 10 to 12 weeks of pregnancy and decreases back to a lower value by 16 to 20 weeks. It continues at this level for the remainder of the pregnancy. Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1058

Question 59

This hormone causes enlargement of the mother’s uterus, (2) enlargement of the mother’s breasts and growth of the breast ductal structure, and (3) enlargement of the mother’s female external genitalia. A. Prolactin B. Oxytocin C. Estrogen D. Progesterone

Answer 59

Answer: C During pregnancy, the extreme quantities of estrogens cause (1) enlargement of the mother’s uterus, (2) enlargement of the mother’s breasts and growth of the breast ductal structure, and (3) enlargement of the mother’s female external genitalia. Reference: Guyton and Hall Textbook of Medical Physiology, 13th ed. p.1060

Question 60

How does the body maintain the testicular temperature? A. It reside inside the abdominal cavity B. It reside outside the pelvic cavity C. It reside outside the abdominal cavity D. it reside inside the pelvic cavity

Answer 60

Answer: C The testes reside outside the abdominal cavity in the scrotum. This location maintains testicular temperature at about 2 degrees lower than body temperature Reference: Berne and Levy Physiology 6th Edition page 1324

Question 61

Which is the following is the function of the Sertoli cells in adults A. It produces testosterone B. It is the 'nurse cell' C. It produce anti-mullerian hormone D. It is responsible in spermatogenesis

Answer 61

Answer: B Sertoli cell is a "nurse cell" in intimate contact with all sperm cells Reference: Berne and Levy Physiology 6th Edition page 1324

Question 62

What is the enzyme that converts small amount of testosterone into the highly potent estradiol? A. CYP 19 B. CYP 17 C. 5 alpha- reductase D. 3β-HSD

Answer 62

Answer: A Sertoli cels express the enzyme CYP19 (aromatase), which converts a small amount of testosterone into the highly potent estrogen estradiol-17β. Reference: Berne and Levy Physiology 6th Edition page 1332

Question 63

What serine protease liquifies coagulated semen after a few minutes? A. Acid phosphatase B. Coagulation factors C. Fructose D. PSA

Answer 63

Answer: D Prostate-specific antigen (PSA) is a serine protease that liquefies coagulated semen after a few minutes. Reference: Berne and Levy Physiology 6th Edition page 1338

Question 64

What part of the egg cell does the sperm bind during fertilization? A. Zona Pelucida B. Basement membrane C. Theca Folliculi D. Cytoplasm

Answer 64

Answer: A The zona pelucida increases in thickness and provides a species specific binding site for sperm during fertilization Reference: Berne and Levy Physiology 6th Edition page 1343

Question 65

In women, what strongly influence the age of the onset of menopause A. Environmental factors B. Genetics C. Physical appearance D. Menarche

Answer 65

Answer: B Age at the onset of menopause has a strong genetic component but is also influenced by environmental factors. Reference: Berne and Levy Physiology 6th Edition page 1343

Question 66

Maintainance of elevated cAMP levels in the mature oocyte will result to A. Ovulation B. Mitotic arrest C. Fertilization D. Meiotic arrest

Answer 66

Answer: D Meiotic arrest is achieved by maintenance of elevated cAMP levels in the mature oocyte Reference: Berne and Levy Physiology 6th Edition page 1345

Question 67

What hormone is necessary for final follicular growth and ovulation? A. FSH B. Estradiol C. LH D. Progesterone

Answer 67

Answer: C LH is necessary for final follicular growth and ovulation. Without this hormone, even when large quantities of FSH are available, the follicle will not progress to the stage of ovulation. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1823

Question 68

What is the effect of estrogen in breast? A. Deposition of fat in breast B. Atrophy of ductile system C. stromal tissues decreases D. lobule and alveoli development

Answer 68

Answer: A Estrogens cause (1) development of the stromal tissues of the breasts, (2) growth of an extensive ductile system, and (3) deposition of fat in the breasts. The lobules and alveoli of the breast develop to a slight extent under the influence of estrogens alone, but it is progesterone and prolactin that cause the ultimate determinative growth and function of these structures. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1830

Question 69

The following are effect of estrogen in fallopian tubes except A. Proliferation of glandular tissue in the lining B. Increase the number of cillia C. Enhance the cilia D. Decrease the number of cilia

Answer 69

Answer: D The estrogens' effect on the mucosal lining of the falopian tubes is similar to that on the uterine endometrium. They cause the glandular tissues of this lining to proliferate; especialy important, they cause the number of ciliated epithelial cels that line the falopian tubes to increase. Also, activity of the cilia is considerably enhanced. These cilia always beat toward the uterus, which helps propel the fertilized ovum in that direction. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1830

Question 70

How long is the entire period of spermatogenesis? A. 21 days B.19 days C. 9 days D. 74 days

Answer 70

Answer: D The entire period of spermatogenesis is 74 days (from spermatogonia to spermatozoa). Reference: Guyton and Hall Medical Physiology 13th ed p.1022

Question 71

Where is the principal site of estrogen synthesis in male? A. Prostate cells B.Leydig cells C. Liver cells D. Spermatocytes

Answer 71

Answer: C Large amounts of estrogen are formed from testosterone and androstenediol in the liver (80% of the total male estrogen production) Reference: Guyton and Hall Medical Physiology 13th ed

Question 72

What is the usual site of fertilization? A.Ovary B. Ampulla of fallopian tubes C cervix D. uterus

Answer 72

Answer: B Fertilization of the ovum normally takes place in one of the ampulla of the fallopian tubes Reference: Guyton and Hall Medical Physiology 13th ed p.1055

Question 73

This hormone is necessary for the final follicular growth and ovulation A.GnRH B.LH C. FSH D.ACTH

Answer 73

Answer: B Without this hormone, the follicle will not progress to the stage of ovulation Reference: Guyton and Hall Medical Physiology 13th ed p.1039

Question 74

What is the major end product of progesterone degradation? A.Pregnanediol B.Osteoprotegerin c. Granulosa cells D. None of the above

Answer 74

Answer: A In the fate of progesterone, about 10% is excreted in the urine in this form Reference: Guyton and Hall Medical Physiology 13th ed p.1044

Question 75

A man suffers from a disease that destroyed only the motor neurons of the spinal cord below the thoracic region. Which of the following would not be possible? A.Ejaculation B.Lubrication C. Arousal D. Erection

Answer 75

Answer: A The motor neurons of the spina cord in the thoracic and lumbar regions are the sources of innervation for the skeletal muscles of the perineum involved in ejaculation Reference: Guyton and Hall Medical Physiology 13th ed p.1027

Question 76

Which of the following is produces by the trophoblast during the 1st 3 weeks of pregnancy? A.Estrogen B. LH C. Oxytocin D. Human chorionic gonadotropin

Answer 76

Answer: D HCG is secreted from the trophoblast cells beginning shortly after the blastocyst implants in the endometrium Reference: Guyton and Hall Medical Physiology 13th ed p. 1059

Question 77

Granulosa cells of the follicle secretes which of the following before the preovulatory stage in LH? A. Testosterone B. Progesterone C. Estrogen D. Inhibin

Answer 77

Answer: C Follicle stimulating hormone stimulates the granulosa cells of the folicle to secrete estrogen Reference: Guyton and Hall Medical Physiology 13th ed p.1040

Question 78

When menstruation ends, estrogen in the blood rises,what is the source of estrogen? A. Corpus luteum B.Ovary C. Developing folicles D. Endometrium

Answer 78

Answer: C Menstruation ends when developing follicles secrete estrogen sufficiently to raise circulating concentration to a level that stimulates regrowth of endometrium Reference: Guyton and Hall Medical Physiology 13th ed p.1040

Question 79

Where does spermatogenesis occur? A. Prostate gland B. Semeniferous tubules C. Ejaculatory duct D. Scrotum

Answer 79

Answer: B Spermatogenesis occurs in semeniferous tubules during active sexual life Reference: Guyton and Hall Medical Physiology 13th ed p.1021

Question 80

Which receptor controls nitric oxide (NO) release to cause vasodilation during penile erection? A. Leptin receptor B. Angiotensin AT1 receptor C. Endothelin ETA receptor D. Muscarinic receptor

Answer 80

Answer: D Parasympathetic postganglionic fibers release acetylcholine that activates muscarinic receptors on endothelium to produce NO and increases cyclic guanosine monophosphate, which activates protein kinase G, causing reduction in intracellular calcium and causing vasodilation. Reference: Guyton and Hall Physiology Review 3rd ed. p.225

Question 81

Which of the following increases secretion of GH? A. Senescence B. IGF-1 C. Somatostatin D. Hypoglycemia

Answer 81

Answer: D Hypoglycemia is a potent stimulus for GH. GH decreases with aging and in response to the hypothalamic inhibitory hormone somatostatin. GH secretion would decreas in response to both exogenous GH administration and IGF-1 as a result of negative feedback inhibition. Reference: Guyton and Hall Physiology Review 3rd ed. p. 226

Question 82

Which of the following could inhibit the initiation of labor? A. Administration of an antagonist of actions of progesterone B. Administration of LH C. Administration of an antagonist of PGE2 effects D. Mechanically dilating and stimulating the cervix

Answer 82

Answer: C Antagonism of progesterone's effects, dilation of the cervix, and oxytocin all increase uterine smooth muscle excitability and facilitate contractions and the onset of labor. LH would have no effect. Prostaglandin E2 strongly stimulates uterine smooth muscle contraction and is formed at an increasing rate by the placenta late in gestation. Reference: Guyton and Hall Physiology Review 3rd ed. p.

Question 83

A birth control compound for men has been sought for several decades. Which substance would provide effective sterility? A. a substance that mimics the actions of LH B. a substance that blocks the actions of inhibin C. a substance that blocks the actions of FSH D. a substance that mimics the actions of GnRH

Answer 83

Answer: C Blocking the action of FSH on the Sertoli cells of the seminiferous tubules interrupts the production of sperm. Reference: Guyton and Hall Physiology Review 3rd ed. p.237

Question 84

During the week after ovulation, the endometrium increases in thickness to 5 to 6 mm. What stimulates the increase in thickness of the endometrium? A. LH B. Estrogen from corpus luteum C. progesterone from corpus luteum D. FSH

Answer 84

Answer: C Progestetone secreted in large quantities from the corpus luteum causes marked swelling and secretory development of the endometrium. Reference: Guyton and Hall Physiology Review 3rd ed. p.238

Question 85

As menstruation ends, estrogen levels in the blood rise rapidly. What is the source of the estrogen? A. Corpus luteum B. Developing follicles C. Endometrium D. Stromal cells of the ovaries

Answer 85

Answer: B Blocking the action of FSH on the Sertoli cells of the seminiferous tubules interrupts the production of sperm. Reference: Guyton and Hall Physiology Review 3rd ed. p.237

Question 86

Blockade of what receptors will prolong erection in the male? A. estrogen receptors B. cholesterol receptors C. muscarinic receptors D. phosphodiesterase-5 receptors

Answer 86

Answer: D Phosphodiesterase-5 receptors prevent hydrolysis of cyclic guanosine monophosphate, thus keeping the levels high and maintaining vasodilation. Reference: Guyton and Hall Physiology Review 3rd ed. p.230

Question 87

Negative feedback on FSH release from the anterior pituitary in men that results in a reduction in estradiol production is due to which hormone? A. Progesterone B. Estradiol C. Testosterone D. Inhibin

Answer 87

Answer: D Inhibin prevents FSH release from the anterior pituitary, preventing sertoli cells from causing aromatization to produce estradiol. Reference: Guyton and Hall Physiology Review 3rd ed. p.230

Question 88

Which of the following is produced by the trophoblast cells during the first 3 weeks of pregnancy? A. Estrogen B. LH C. Oxytocin D. HCG

Answer 88

Answer: D HCG is secreted from the trophoblast cells beginning shortly after the blastocyst implants in the endometrium. Reference: Guyton and Hall Physiology Review 3rd ed. p.233

Question 89

A man has a disease that destroyed only the motor neurons of the spinal cord below the thoracic region. Which aspect of sexual function would not be possible? A. Arousal B. Erection C. Lubrication D. Ejaculation

Answer 89

Answer: D The motor neurons of the spinal cord of the thoracic and lumbar regions are the sources of innervation for the skeletal muscles of the perineum involved in ejaculation Reference: Guyton and Hall Physiology Review 3rd ed. p.236

Question 90

Why does Meiosis II occur in Spermatogenesis? A. So that only half of the genetic characteristics of the eventual fetus are provided by the father B. So that the 46 chromosomes of the spermatocytes are divided C. To form secondary spermatocytes D. To form primary spermatocytes

Answer 90

Answer: A The chromosomal genes are also divided so that only one half of the genetic characteristics of the eventual fetus are provided by the father, with the other half being derived from the oocyte provided by the mother. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1022

Question 91

The entire period of spermatogenesis takes about how many days? A. 73 days B. 74 days C. 63 days D. 64 days

Answer 91

Answer: B The entire period of spermatogenesis , from spermatogonia to spermatozoa, takes about 74 days. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1022

Question 92

The thick gap on the outside of the anterior 2/3 of the head of the sperm which contains enzymes that allow the sperm to enter the ovum. A. Flagellum B. Acrosome C. Axoneme D. Microtubules

Answer 92

Answer: B On the outside of the anterior 2/3 of the head of the sperm is a thick gap called the acrosome. It containes several enzymes such as hyaluronidase (which can digest proteoglycan filaments of tissues) and powerful proteolytic enzymes (which can digest proteins). These enzymes play important roles in allowing the sperm to enter the ovum and fertilize it. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1023

Question 93

The hormone secreted by the anterior pituitary gland which stimulatedsthe Leydig cells to secrete testosterone. A. FSH B. LH C. GH D. Estrogen

Answer 93

Answer: B Luteinizing hormone is secreted by the anterior pituitary gland which stimulated the Leydig cells to secrete testosterone. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1023

Question 94

The hormone secreted by the anterior pituitary gland which stimulates the Sertoli cells. A. FSH B. LH C. GH D. Estrogen

Answer 94

Answer: A Also secreted by anterior pituitary gland, stimulated the Sertoli cells; Conversion of spermatids to sperm. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1023

Question 95

What is defective in the male sperm in Kartagener Syndrome? A. Flagellum B. Acrosome C. Anterior Head Cap D. Posterior Head Cap

Answer 95

Answer: A Kartagener syndrome (Primary ciliary dyskinesia), is a rare, ciliopathic, autosomal recessive genetic disorder that causes defects in the action of cilia lining the respiratory tract (lower and upper, sinuses, Eustachian tube, middle ear) and fallopian tube, as well as in the flagella of sperm cells. Reference: Dr. Calderon's Lecture

Question 96

Which enzyme relaxes the arteries of the penis causing pooling of blood and further vasodilation in the penis? A. Nitric oxide B. Guanylyl cyclase C. cGMP D. Camp

Answer 96

Answer: C The cyclic cGMP especially relaxes the arteries of the penis and the trabecular meshwork of smooth muscle fibers in the erectile tissue of the penis. As the vascular smooth muscles relax, blood flow into the penis increases, causing release of nitric oxide from the vascular endothelial cells and further vasodilation. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1027

Question 97

During oogenesis, at what phase does the primary oocyte arrest until ovulation? A. Prophase I B. Prophase II C. Metaphase I D. Metaphase II

Answer 97

Answer: A Meiosis begins but levels of preoteins required for completion are too low ─ primary oocyte arrests at prophase I. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1038

Question 98

At what phase is secondary oocyte arrested until fertilization? A. Prophase I B. Prophase II C. Metaphase I D. Metaphase II

Answer 98

Answer: D A few hours after ovulation, oocyte completes Meiosis I and Meiosis II is arrested at Metaphase II until fertilization. Reference: Guyton & Hall: Textbook of Medical Physiology 12th ed page 1038

Question 99

Where in the oviducts does fertilization usually occur? A. Ampullary-isthmus junction B. Ampulla C. Isthmus D. Intramural segment

Answer 99

Answer: A Ampullary-isthmus junction is the site where fertilization occurs. Reference: Dr. Calderon's Lecture/Guyton & Hall: Textbook of Medical Physiology 12th ed page 1055

Question 100

The testosterone that does not become fixed to the tissues is converted into what? A. Androsterone B. Dehydroepiandrosterone C. Both A & B D. None of the above

Answer 100

Answer: C The testosterone that does not become fixed to the tissues is converted rapidly into androsterone and dehydroepiandrosterone mainly by the liver. Reference: Guyton and Hall: Textbook of Medical Physiology p.1028

Question 101

What will happen if gonadotropic hormones are administered to a newborn child? A. Nothing will happen B. There will be an increase in protein formation. C. The muscles of the newborn child will develop rapidly D. It will cause the testes to descend

Answer 101

Answer: D Gonadotropic hormones stimulate the Leydig cells of the newborn child’s testes, producing testosterone. This will cause the testis to descend. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1029-1030

Question 102

This hormone contributes to the development of acne in male adolescents. A. Estrogen B. Testosterone C. Androstenedione D. All of the above

Answer 102

Answer: B Testosterone increases the rate of secretion of the body’s sebaceous glands, especially by the sebaceous glands of the face which contributes to the development of acne. Acne is one of the most common features in male adolescents when the body is first becoming introduced to the increase in testosterone. However, the skin adapts normally to the secretion of testosterone, after several years, in a way that allows it to overcome acne. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1030

Question 103

What is the effect of an increase in LH to the regulation of testosterone? A. An increase in LH decreases testosterone secretion B. An increase in LH increases testosterone C. An increase in LH will have no effect of testosterone D. An increase in LH is not connected in any way to the regulation of testosterone secretion

Answer 103

Answer: B Testosterone is secreted by the interstitial cells of Leydig in the testis. This secretion by the interstitial cells of Leydig is stimulated by LH from the anterior pituitary gland. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1032

Question 104

Why does diminished liver function cause hyperestrinism? A. Diminished liver function increases the oestrogen's activity in the body B. Diminished liver function will not be able to conjugate estrogen C. Diminished liver function does not cause hyperestrinism D. Both A & B are correct

Answer 104

Answer: D The liver conjugates the oestrogen's to form glucuronides and sulphates. About one-fifth of these conjugated products is excreted in the bile, and most of the remainder is excreted in the urine. Also, the liver converts the potent oestrogen's estradiol and estrone into the almost totally impotent oestrogen estriol. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1044

Question 105

A deficiency in oestrogen after menopause leads to: A. Increase in osteoclastic activity, decrease in bone matrix, increase in deposition of bone calcium and phosphate B. Increase in osteoclastic activity, increase in bone matrix, increase in deposition of bone calcium and phosphate C. Increase in osteoclastic activity, decrease in bone matrix, decrease in deposition of bone calcium and phosphate D. Decrease in osteoclastic activity, decrease in bone matrix, Decrease in deposition of bone calcium and phosphate

Answer 105

Answer: C Almost no oestrogen's are secreted by the ovaries after menopause. This oestrogen deficiency leads to an increase in osteoclastic activity, decrease in bone matrix, and decrease in deposition of bone calcium and phosphate. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1045

Question 106

This is the onset of adult sexual life. A. Menarche B. Puberty C. Ovulation D. Fertilization

Answer 106

Answer: B The period of puberty is caused by a gradual increase in the secretion of gonadotropic hormones by the pituitary. It begins in about the eighth year of life. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1050

Question 107

What is the effect of parasympathetic signal on the arteries of erectile tissue on the early phases of sexual stimulation in females? A. Constriction of arteries of the erectile tissue B. Dilation of arteries of the erectile tissue C. Sympathetic signals are responsible for the erection of female tissue D. None of the above

Answer 107

Answer: B The erectile tissue is innervated by parasympathetic nerves, and in the early phases of sexual stimulation, it dilates the arteries of the erectile tissue. This dilation allows rapid accumulation of blood in the erectile tissue so that the introits tightens around the penis, which aids the male in his attainment of sufficient sexual stimulation for ejaculation to occur, Reference: Guyton and Hall: Textbook of Medical Physiology p. 1052

Question 108

Stimulation of FSH and LH receptors to combine with the membranes of ovarian target cells causes an increase in the cells’ secretion rates and the growth and proliferation of the cells. This stimulatory effect is caused by: A. Activation of cyclic adenosine monophosphate B. Activation of cyclic guanosine monophosphate C. Both A & B D. None of the above

Answer 108

Answer: A The activation of cyclic adenosine monophosphate stimulates the FSH and LH receptors to combine with the membranes in the ovarian target cell. In turn, the activated receptors increase the cells’ secretion rates and growth and proliferation of the cells. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1039

Question 109

In the blastocyst stage, the stromal cells and the epithelial cells proliferate rapidly. A. True B. False

Answer 109

Answer: B In the blastocyst stage, the trophoblastic cells on the surface of the implanting ovum begin to digest the endometrium and absorb the endometrial stored substances, making great quantities of nutrients available to the early implanting embryo. Reference: Guyton and Hall: Textbook of Medical Physiology p. 1047

Question 110

Which of the following can cause sterility in males? A.Excessive temperature of the testes B. Ejaculation C.Using Viagra D. None of the above

Answer 110

Answer: A Increasing the temperature of the testes can prevent spermatogenesis by causing degeneration of most cells of the seminiferous tubules besides the spermatogonia.The scrotum acts as a cooling mechanism for the testes (but a controlled cooling), without which spermatogenesis might be deficient during hot weather. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(80):977

Question 111

Which is secreted by the Leydig cells located in the interstitium of the testis, essential for growth and division of the testicular germinal cells? A. Luteinizing hormone B. Follicle- stimulating hormone. C. Testosterone D. Estrogen

Answer 111

Answer: C Testosterone, secreted by the Leydig cells located in the interstitium of the testis, is essential for growth and division of the testicular germinal cells, which is the first stage in forming sperm. While Luteinizing hormone, secreted by the anterior pituitary gland, stimulates the Leydig cells to secrete testosterone. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(80):975

Question 112

How long/ how many days does it take for female fertility period last each month? A. 10-13 B. 2-3 C. 9-11 D. 4-5

Answer 112

Answer: D The ovum remains viable and capable of being fertilized after it is expelled from the ovary probably no longer than 24 hours. Therefore, sperm must be available soon after ovulation if fertilization is to take place. A few sperm can remain fertile in the female reproductive tract for up to 5 days. Therefore, for fertilization to take place, intercourse must occur sometime between 4 and 5 days before ovulation up to a few hours after ovulation. Thus, the period of female fertility during each month is short, about 4 to 5 days. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(81):1001

Question 113

Means the onset of adult sexual life? A. Puberty B. Menopause C. Ovulation D. Klinefelter syndrome

Answer 113

Answer: A The period of puberty is caused by a gradual increase in gonadotropic hormone secretion by the pituitary, beginning in about the eighth year of life and usually culminating in the onset of puberty and menstruation between ages 11 and 16 years in girls (average, 13 years). Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(81):998

Question 114

Another term for "burning out" of the ovaries? A. Puberty B. Menopause C. Ovulation D. Menarche

Answer 114

Answer: B The period during which the menstrual cycle ceases and the female sex hormones diminish to almost none is called menopause. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(81):999

Question 115

Which of the following is not secreted by the prostate gland? A. Fibrinolysin B. Profibrinolysin C. Calcium D. Citrate ion

Answer 115

Answer: A The prostate gland secretes a thin, milky fluid that contains calcium, citrate ion, phosphate ion,a clotting enzyme, and a profibrinolysin. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(80):976

Question 116

How long does an entire period of spermatogenesis last?(in days) A.35 B. 60 C. 74 D. 86

Answer 116

Answer: C The entire period of spermatogenesis, from spermatogonia to spermatozoa, takes about 74 days. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(80):974

Question 117

What sex does an XX chromosome combination give? A. Male B. Female C. Cannot be determined D. None of the above

Answer 117

Answer: B After formation of the mature sperm, half of these carry in their genome an X chromosome (the female chromosome) and half carry a Y chromosome (the male chromosome). Therefore, if an X chromosome from a sperm combines with an X chromosome from an ovum, giving an XX combination, a female child will be born, but if a Y chromosome from a sperm is paired with an X chromosome from an ovum, giving an XY combination, a male child will be born. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(82):1004

Question 118

Which of the following does not happen during pregnancy. A. Decrease aldosterone B. increase in HCG C. Secretion of Relaxin D. None of the above

Answer 118

Answer: A Almost all the nonsexual endocrine glands of the mother also react markedly to pregnancy. This results mainly from the increased metabolic load on the mother but also, to some extent, from the effects of placental hormones on the pituitary and other glands. These include:Pituitary Secretion,Increased Corticosteroid Secretion,Increased Thyroid Gland Secretion, Increased Parathyroid Gland Secretion, Secretion of "Relaxin" by the ovaries and placenta. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(82):1009

Question 119

Which of the statements is incorrect? During pregnancy, A. Production of corticotropin increases B. Production of thyrotropin increases C. Production of prolactin increases D. Production of luteinizing hormone increases

Answer 119

Answer: D The anterior pituitary gland of the mother enlarges at least 50 percent during pregnancy and increases its production of corticotropin, thyrotropin, and prolactin. Conversely, pituitary secretion of folliclestimulating hormone and luteinizing hormone is almost totally suppressed as a result of the inhibitory effects of estrogens and progesterone from the placenta. Reference: GUYTON, A.C., HALL, J.E.2011.Textbook of Medical Physiology.12th Ed. 14(82):1009

Question 120

What is the sex chromosome of Females ? A. XY B. XX C. YY D. ZZ

Answer 120

Answer: B There's no YY and ZZ sex chromosomes, while XY is the genetic sex for males Reference: Linda costanzo pp 447

Question 121

What cells secerete Testosterone ? A. Sertoli cells B.Leydig cells C. Both sertoli cells and Leydig cells D. None

Answer 121

Answer: B Leydig cells produce testosterone, while sertoli cells produce glycoprotein hormone Reference: Linda costanzo pp 452

Question 122

Human sex cells are haploid cells. A. TRUE B. FALSE

Answer 122

Answer: B Human beings are diploid cells, by merging two haploid cells Reference: Linda costanzo pp 447

Question 123

Cells develop 5-alpha reductase activity until they have fully differentiated and it is required for conversion of testosterone to dihydrotestosterone A. The 1st statement is correct B. The 2nd statement is correct C. Both statements are correct D. Both statements are wrong

Answer 123

Answer: B Alpha reductase do not develop untill they're fully differentiated Reference: Linda Costanzo pp 453

Question 124

Levels of which of the following hormones are high during the first trimester of pregnancy and decline during the second and third trimesters? A. Adrenocorticotropic hormone (ACTH) B. Estradiol C. Human chorionic gonadotropin (HCG) D.Oxytonin

Answer 124

Answer: C During the first trimester of pregnancy, the placenta produces human chorionic gonadotropin (HCG), which stimulates estrogen and progesterone production by the corpus luteum. Peak levels of HCG occur at about the ninth gestational week, and then decline. At the time of the decline in HCG, the placenta assumes the responsibility for steroidogenesis for the remainder of the pregnancy Reference: Linda costanzo pp 464

Question 125

One of action of dihydrotestosterone is for the growth of prostate while one ac tion of testosterone is for the dfifferentiation of penis, scrotum, and prostate. A. The 1st statement is correct B. The 2nd statement is correct C. Both statements are correct D. Both statements are wrong

Answer 125

Answer: A Both are action of dihyrotestosterone Reference: Linda costanzo pp 454-455

Question 126

Lactation occur during pregnancy because estrogen and progesterone will allow the. action of prolactin on the breast A. TRUE B. FALSE

Answer 126

Answer: B Estrogen and progesterone will block the action of prolactin Reference: Linda costanzo pp 465

Question 127

Minda a 32 year old woman has the anterior lobe of her pituitary gland surgically removed because of a tumor. Without hormone replacement therapy, which of the following would occur after the operation A. Absence of menses B.Inability to concentrate the urine in response to water deprivation C. Failure to secrete catecholamines in response to stress D. Failure to secrete insulin in a glucose tolerance test

Answer 127

Answer: A ``` Normal menstrual cycles depend on the secretion of follicle- stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary. ``` Reference: Linda costanzo pp 459-460

Question 128

Mang Jose a 40 year old man has a prostate surgery,and it casue trauma to the parasympathetic nerves. Which of the following will occur ? A. Increase in testosterone level B. Erectile dysfunction C. Increase sexual arousal D. Prolong errection

Answer 128

Answer: B Parasymphathetic nerves will stimulate errection Reference: Linda costanzo pp 454-455

Question 129

Michelle a 17-year-old, seemingly normal female is diagnosed with androgen insensitivity disorder. She has never had a menstrual cycle and is found to have a blindending vagina; no uterus, cervix, or ovaries; a 46 XY genotype; and intraabdominal testes. Her serum testosterone is elevated. Which of the following characteristics is caused by lack of androgen receptors? A. 46 XY genotype B. Testes C. Elevated serum testosterone D. Lack of uterus and cervix

Answer 129

Answer: C The elevated serum testosterone is due to lack of androgen receptors on the anterior pituitary (which normally would mediate negative feedback by testosterone) Reference: Linda costanzo pp 454

Question 130

In females with a regular cycle, ovulation occurs: A. 14 days after the onset of menstruation B. 14 days after the last day of menstruation C. 7 days after the onset of menstruation D. 7 days after the last day of menstruation

Answer 130

Answer: A "Ovulation in a woman who has a normal 28-day female sexual cycle occurs 14 days after the onset of menstruation." Reference: Guyton and Hall Medical Physiology, 13th ed, p.1041

Question 131

Primordial germ cells that migrate into testis become A. Oogonia B. Sperm cell C. Spermatogonia D. Primary sperm

Answer 131

Answer: C During embryonic development, primordial germ cells develop into spermatogonia once they enter the testis. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1022

Question 132

After ovulation, the remaining cells of the ruptured follicle are transformed into a glandular structure called A. Cumulus oophorous B. Corpus luteum C. Corpus albicans D. None of the above

Answer 132

Answer: C After expulsion of the ovum from the follicle, the remaining granulosa and theca interna cells are luteinized. The total mass of theca lutein and granulosa lutein cells form the corpus luteum. Reference: Essentials of Anatomy and Physiology, 6th ed, p.556

Question 133

Contraction of these structures is responsible for milk ejection A. Sertoli cells B. Myoepithelial cells C. Myometrium D. Nipples

Answer 133

Answer: B Once triggered by oxytocin, myoepithelial cells contract for milk ejection to occur. Reference: Essentials of Anatomy and Physiology, 6th ed, p.561

Question 134

Testosterone, a hormone important in male reproduction, is secreted by ____ located in the ____ of the testis. A. Sertoli cells; anterior portion B. Leydig cells; anterior portion C. Leydig cells; interstitium D. Sertoli cells; interstitium

Answer 134

Answer: C Leydig cells are responsible for testosterone production, and they are located in the interstitium of the testis. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1023

Question 135

Testosterone affects the following, except: A. electrolyte and water balance B. calcium retention C. body hair distribution D. none of the above

Answer 135

Answer: D Testosterone has an effect on choices a-c. For the electrolyte and water balance, the said hormone increases the sodium reabsorption in the distal tubules. Testosterone also causes calcium retention, since it increases the total quantity of bone matrix during puberty. In addition, testosterone causes hair growth in areas like the face, over the pubis, and along the linea alba. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1030-1031

Question 136

Mucus that supplies the urethra in males is derived from: A. Cowper glands B. Sertoli glands C. Muller’s glands D. Glands of Bartholin

Answer 136

Answer: A Also known as bulbourethral glands, Cowper glands located within the origin of the urethra, supplies mucus to the urethra. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1021

Question 137

The transformation of primary spermatocyte into secondary spermatocyte occurs through ____, and is completed within ____ days. A. Meitotic division 1; 9 B. Meiosis; 21 C. Meitotic division 2; 21 D. Meitotic division 2; 9

Answer 137

Answer: A In order for the primary spermatocyte to develop into secondary spermatocyte, it must undergo mitotic division I. The process is completed in about 9 days. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1022

Question 138

Which among the statements regarding Luteinizing Hormone is/are true? I. In the absence of LH, follicle will progress to ovulation stage, as long as there is sufficient amount of FSH II. LH is secreted by the anterior pituitary gland III. Increase in LH secretion peaks 2 days before ovulation A. I and II B. I and III C. I only D. II only

Answer 138

Answer: D Only statement II is true. Statement II is false, since LH is needed for the maturation of follicles. Even if FSH is present in high amounts, follicle won’t progress to ovulation stage if LH is absent. Statement III is also false, since the peak of the rise in LH secretion happens 16 hours before ovulation. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1041

Question 139

Which among the statements regarding sperm is/are true? I. Sperm activity is greatly enhanced in acidic medium II. At body temperature, ejaculated sperm can last for 2 weeks III. Acrosome of the sperm contains large amounts of hyaluronidase and preteolytic enzymes A. I and II B. I only C. I, II, AND III D. III only

Answer 139

Answer: D Only Statement III is true. Statement I is false, since enhanced sperm activity is associated with neutral and slightly alkaline conditions. Statement II is also false, since once ejaculated, human sperm only has a lifespan of 24-48 hours. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1023-1025

Question 140

In the absence of this hormone will lead to severely deficient spermatogenesis, thus, causing infertility. A. LH B. FSH C. Testosterone D. Growth hormone

Answer 140

Answer: D Growth hormone is specifically responsible for early division of spermatogonia, thus, the absence of it will lead to deficient or absent spermatogenesis Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1806

Question 141

It is an important enzyme which highly contribute to the ability of sperm cell to reach the ovum. A. Proteolytic enzymes B. Hyaluronidase C. Acid phosphatase D. Alkaline phosphatase

Answer 141

Answer: B Hyaluronidase allows the opening of pathways between the granulosa cells, therefore, allowing the sperm cell to reach the ovum Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1808

Question 142

All of the following conditions increases secretion of testosterone, except: A. When tumors develop from interstitial cells of Leydig B. During first few months of newborn male infant C. During childhood D. During male adulthood, after puberty

Answer 142

Answer: C During childhood, Leydig cells are almost nonexistent in the testes and the testes secrete almost no testosterone Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1813

Question 143

Besides testosterone, what is the other hormone necessary to initiate spermatogenesis? A. Follicle stimulating hormone B. Androstenedione C. Luteinizing hormone D. Estrogen

Answer 143

Answer: A Follicle stimulating hormone is the one which causes Sertoli cells to grow and secrete various spermatogenic substances Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1820

Question 144

Which is TRUE about the ovarian cycle? A. All follicles undergo atresia after a month B. Only one follicle undergoes atresia after a month C. All follicles will become fully mature after a month D. Only one follicle fully matures after a month

Answer 144

Answer: D Only one follicle matures each month and the remainder undergo atresia Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1834

Question 145

What change happens to a follicle upon secretion of follicular fluid? A. Increased in layer of granulosa cells B. Degeneration of the zona pellucida C. Appearance of antrum within the mass of granulosa cells D. Atresia of the ovarian stroma

Answer 145

Answer: C Accumulation of follicular fluid leads to formation of antrum in order to find space for it to be contained Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1834

Question 146

It is a structure formed during ovulation which secretes high amounts of female sex hormones A. Corpus luteum B. Corpus albicans C. Antrum D. Zona pellucida

Answer 146

Answer: A Copus luteum is a highly secretory organ which secretes large amounts of both progesterone and estrogen during the LH or ovulatory surge Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1836

Question 147

All statements are TRUE about female sex hormones, except: A. During synthesis, mainly progesterone and androgens are synthesized FIRST B. Both granulosa cells and theca cells can convert androgens to estrogens C. During follicular phase of the ovarian cycle, almost all androgens and much of progesterone are converted to estrogen D. Aromatase is the enzyme responsible for conversion of androgens to estrogens

Answer 147

Answer: B Unlike granulosa cells, the theca cells lack the enzyme aromatase which converts androgens to estrogens Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1839

Question 148

All of the following stages constitutes the endometrial cycle, except: A. Sloughing of the whole endometrium B. Development of secretory changes in the endometrium C. Proliferation of the uterine endometrium D. Menstruation or desquamation of the endometrium

Answer 148

Answer: A Only the functional layer of the endometrium is sloughed off during menstruation Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1843

Question 149

Fatigue, irritability, psychic sensations of dyspnea, and decreased strength & calcification of bones experienced by women are mainly caused by: A. Increased in both progesterone and estrogen B. Decreased in both progesterone and estrogen C. Loss of progesterone D. Loss of estrogen

Answer 149

Answer: D During menopausal stage, loss of estrogen in women causes marked physiological changes in the function of the body Reference: Guyton and Hall Medical Physiology, 12th ed, p. 1850

Question 150

Testoterone begins to elaborate at about _____ week of embryonic life A. 6th B. 7th C.8th D. 9th

Answer 150

Answer: B During fetal development, testosterone begins to elaborate by the 7th week and is responsible for the development of male body characteristics and suppressing female genital organs. Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1029

Question 151

The thick cap in the anterior two-thirds of the head of the sperm cell is formed mainly from _______. A. Nucleus B. Mitochondria C. Cytoplasm D. Golgi apparatus

Answer 151

Answer: D On the outside of the antierior two-thirds of the head of the sperm cell is the thick cap called acrosome that is mainly from golgi apparatu Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1023

Question 152

The principal estrogen secreted by the ovaries is ______. A. Estrone B. Estradiol C. Estriol D. Progestin

Answer 152

Answer: B Estradiol is the principal estrogen sereted by the ovaries and small anounts of estone are also secreted; estriol is a weak estrogenderived from both estradiol and estrone with conversion occurs mainly+M20 in the liver Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1043

Question 153

At the time of ovulation, the endometrium is ______ mm thick. A. 3-5 B. 4-6 C. 1-3 D. 2-5

Answer 153

Answer: A At the time of ovulation the endometrium is 3-5 mm thick. Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1046

Question 154

The ______ especailly relaxes the arteries of the penis and the trabecular meshwork of smooth muscle fibers in the erectile tissue of the corpus cavernosa and corpus spongiosum. A. cyclic AMP B. cyclic GMP C. Either D. Neither

Answer 154

Answer: B The cyclic AMP especially relaxes the arteries of the penis and trabecular meshwork of smooth muscle fibers in the erectile tissue in the corpus cavernosum and corpus spongiosum of the shaft of the penis. Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1027

Question 155

_______ specifically promotes early division of spermatogonia A. testosterone B. LH C. GH D. FSH

Answer 155

Answer: C Growth hormone specifically promotes early division of spermatogonia; in its absence, the spermatogenesis is severely deficient or absent, causing infertilty Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1023

Question 156

Diffusion of oxygen thorugh maternal placenta is by ______________. A. Simple diffiusion B. Facillitated diffusion C. Co-transport D. Carrier-mediated transport

Answer 156

Answer: A The dissolve oxygen in the blood of the large maternal sinuses passes into the fetal blood by simple diffusion, driven by an oxygen pressure gradient from the mother's blood to the fetus's blood Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1058

Question 157

The extreme solubility of carbon dioxide in the placental membrane allows carbon dioxide to diffuse about ______ times as rapid as oxygen. A.10 B. 15 C. 20 D. 25

Answer 157

Answer: A The small pressure gradient for carbon dioxide is more than sufficient to allow adequate diffusion of carbon dioxide because the extreme solubility of carbon dioxide in the placental membrane allows carbon dioxide to diffuse about 20 times as rapid as oxygen. Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1059

Question 158

The changes that occur in capacitation I. The uterine and fallopian tube fluids wash away various inhibitory factors that suppress sperm activity in the male genital ducts II. After ejaculation the sperm deposited in the vagina swim away from the cholesterol vesicles to the uterine cavity. III. The membrane of the sperm becomes much permeable to Mg, enters the sperm in abundance and changes the activity of flagellum to a powerful whip-like motion. A. I, II, III B. I, II C. I only D. I and III only

Answer 158

Answer: B I. The uterine and fallopian tube fluids wash away various inhibitory factors that suppress sperm activity in the male genital ducts II. After ejaculation the sperm deposited in the vagina swim away from the cholesterol vesicles to the uterine cavity. III. The membrane of the sperm becomes much permeable to Mg, enters the sperm in abundance and changes the activity of flagellum to a powerful whip-like motion. Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1025

Question 159

The following promotes growth of the ductal system of the breast except: A. Insulin B. Growth hormone C. Prolactin D. Oxytocin

Answer 159

Answer: D Also imporant for growth of the ductal system are at least 4 other hormones: growth hormone, prolactin, the adrenal glucocorticoids, and insulin. Reference: Textbook of Medical Physiology by Guyton and Hall 13th Edition p. 1066

Question 160

True of determining Region of Y chromosome (SRY): I – testis determining gene product II – DNA – binding regulatory protein III – located near the tip of the short arm of Y chromosome IV – located near the tip of the long arm of the X chromosome A. I, II B. I, II, III C. II,III D. All except III

Answer 160

Answer: B Sex determining Region of Y chromosome (SRY) is the testis determining gene product that is a DNA-binding regulatory protein. It is located near the tip of the short arm of Y chromosome NOT in the long arm of the X chromosome. Reference: Review of Medical Physiology, 23rd ed.

Question 161

What is the enzyme that catalyzes the reduction of testosterone to its active form, dihydrotesterone? A. β-galactosidase B. 5,α-reductase C. Adenylyl cyclase D. None of the above

Answer 161

Answer: B 5,α-reductase catalyzes the reduction of testosterone to DHT β-galactosidase catalyzes the hydrolysis of lactose to galactose and glucose Adenyly cyclase catalyzes the conversion of ATP to cyclic AMP Reference: Review of Medical Physiology, 23rd ed. , Page 397

Question 162

What is the correct sequence of events that could happen to a female following puberty? A. Thelarche, Pubarche, Menarche B. Menarche, Thelarche, Pubarche C. Thelarche, Menarche, Pubarche D. Pubarche, Menarche, Thelarche

Answer 162

Answer: A Following puberty, the first event that will happen in females is thelarche, the development of breasts, followed by pubarche, the development of axillary and pubic hair, and then by menarche, the first menstrual period. Reference: Review of Medical Physiology, 23rd ed. Page 398

Question 163

Which of the following are the is/are effects of estrogen on the female genitalia? A. All of the above B. Increase uterine blood flow and increase the amount of uterine muscle and its content of contractile proteins. C. Does not cause cyclic changes in the endometrium, cervix, and vagina. D. None in the choices

Answer 163

Answer: B Estrogens facilitate the growth of the ovarian follicles and increase the motility of the uterine tubes. It causes cyclic changes in the endometrium, cervix, and increase uterine blood flow. It increases the amount of uterine muscle and its content of contractile proteins. Under the influence of estrogens, the muscle becomes more active and excitable, and action potentials in the individual fibers become more frequent. Reference: Review of Medical Physiology, 23rd ed. Page 407

Question 164

A 68-year-old man was brought to the hospital with a chief complaint of difficulty in urinating and urinates more often at night. He also noticed that there is blood in his urine. Physical exam was normal and the digital rectal examination revealed a slightly enlarged prostate. The doctor suspected of prostate cancer. Which of the following substances is increased can be detected in the blood of the patient? A. Zinc B. Acid phosphatase C. Prostate-specific antigen D. Alkaline phosphatase

Answer 164

Answer: C Zinc and acid phosphatase are produced by the prostate gland but are not increased in patients with prostate cancer. PSA (protate-specific antigen) is, specific, increased and can be detected in the blood of the patients with prostate cancer. Reference: Berne & Levy Physiology, 6th ed. page 767

Question 165

Which of the following is/are false about progesterone? I – opposes the proliferative actions of estradiol-17β II – induces inactivating isoforms of 17 β-HSD III – does not convert the active estradiol-17β into the inactive estrone IV – supports the actions of estradiol-17β V - down-regulates the estrogen receptor A. I and II B. II and IV C. III and IV D. II, III, IV

Answer 165

Answer: C Progesterpne opposes the proliferative actions of estradiol-17β and down-regulates the estrogen receptor. It also induces induces inactivating isoforms of 17 β-HSD, thereby converting the active estradiol-17β into the inactive estrone. This opposition of the mitogenic actions of estradiol-17β by progesterone is important to protect the uterine endometrium from estrogen-induced uterine cancer. Reference: Berne & Levy Physiology, 6th ed. page 782

Question 166

Which of the following is the correct sequence/arrangement of events that occur to achieve successful fertilization? I – penetration of the expanded cumulus by the sperm II – Ca++ signaling cascade III – penetration of the zona pellucid by the sperm IV – the entire sperm enters the egg during fusion. The flagellum and mitochondria disintegrate. V – fusion of the sperm and egg membrane takes place VI – signaling cascade activates the exocytosis of the enzyme-filled vesicles. A. I, II, III, IV, V, VI B. IV, III, VI, V, II, I C. I, III, V, II, VI, IV D. I, III , II, V, VI, IV

Answer 166

Answer: C Fertilization accomplishes both recombination of genetic material to form a new, genetically distinct organism and initiation of events that begin embryonic development. The several steps must occur to achieve successful fertilization: (1) Penetration of the expanded cumulus by the sperm (2) Penetration of zona pellucid by the sperm (3) Fusion of the sperm and egg membrane takes place. (4) Ca++ signaling cascade occurs. (5) The signaling cascade activates the excoytosis of enzyme-filled vesicles. (6) the entire sperm enters the egg during fusion. The flagella and mitochondria disintegrate. Reference: Berne & Levy Physiology, 6th ed. page 785

Question 167

After ovulation, the corpus luteum produces high progesterone with estradiol-17β. Estradiol-17β inhibits further endometrial growth and induces the differentiation of epithelial and stromal cells. A. True B. False

Answer 167

Answer: B Progesterone is the one that inhibits further endometrial growth and induces the differentiation of epithelial and stromal cells. Reference: Berne & Levy Physiology, 6th ed. page 780

Question 168

Which of the following is NOT the main function of uterine tube? A. Provide site for sperm storage B. Secrete fluids that provide nutritional support to the preimplantation embryo C. Capture the cumulus-oocyte complex at ovulation D. Assist the movement of sperm from the vagina.

Answer 168

Answer: D The first 3 choices are the main functions of the uterine tube. Uterus assist the movement of sperm from the vagina Reference: Berne & Levy Physiology, 6th ed. page 779

Question 169

Sertoli cells are the true epithelial cells of the seminiferous epithelium and extend from the basal lamina to the lumen. An important structural feature of Sertoli cells is the formation of tight junctions between adjacent Sertoli cells. A. True B. False

Answer 169

Answer: A An important structural feature of Sertoli cells is the formation of tight junctions between adjacent Sertoli cells, thus form the physical basis for the blood-testis-barrier. Reference: Berne & Levy Physiology, 6th ed. page 760-761

Question 170

The testes, the male gonads, consist of three cell types and one of it is Leydig cells which is know to synthesize what hormone? ``` A. Testosterone B. Antimüllerian Hormone C. Spermatogonia D. Gonadotropin-releasing hormone (GnRH) ```

Answer 170

Answer: A The germ cells produce spermatogonia, the Sertoli cells synthesize a glycoprotein hormone called antimüllerian hormone, and the Leydig cells synthesize testosterone. Reference: Linda Constanzo p.447

Question 171

What consists the internal genitalia In females? A. The fallopian tubes, uterus, and upper one fourth of the vagina. B. The fallopian tubes, uterus, and upper one third of the vagina. C. The fallopian tubes, uterus, and upper half of the vagina. D. The fallopian tubes, uterus, and lower one third of the vagina.

Answer 171

Answer: B The female internal genitalia includes the fallopian tubes, uterus, and upper one third of the vagina Reference: Linda Constanzo p.449

Question 172

The source of estrogen during the second and third trimesters of pregnancy is the? A. Corpus luteum B. Fetal adrenal gland, fetal liver, and placenta C. Maternal adrenal gland and fetal liver D. Maternal ovaries and fetal adrenal gland

Answer 172

Answer: B During the second and third trimesters of pregnancy, the fetal adrenal gland synthesizes dehydroepiandrosterone-sulfate (DHEA-S), which is hydroxylated in the fetal liver and then transferred to the placenta, where it is aromatized to estrogen. In the first trimester, the corpus luteum is the source of both estrogen and progesterone. Reference: BRS Physiology p.259

Question 173

How many hours does the sperm need to reside in the female reproductive tract in order for capacitation to occur? A. 4 to 6 hours B. 72 hours C.12-24 hours D. 1 hour

Answer 173

Answer: A Ejaculated sperm cannot immediately fertilize an ovum: They must reside in the female reproductive tract for 4 to 6 hours for capacitation to occur. Capacitation is a process in which inhibitory factors in the seminal fluid are washed free, cholesterol is withdrawn from the sperm membrane, and surface proteins are redistributed. Reference: Linda Constanzo p.453

Question 174

In males, what does the internal genital tract includes? A. Prostate ONLY B. Seminal vesicles and vas deferens ONLY C. Prostate, seminal vesicles, vas deferens, and epididymis. ONLY D. Vas deferens and epididymis ONLY

Answer 174

Answer: C In males, the internal genital tract includes the prostate, seminal vesicles, vas deferens, and epididymis. Reference: Linda Constanzo p.448

Question 175

What consists the internal genitalia In females? A. Fallopian tubes, uterus, and upper one fourth of the vagina. B. The Fallopian tubes, uterus, and upper one third of the vagina. C. The Fallopian tubes, uterus, and upper half of the vagina. D. The Fallopian tubes, uterus, and lower one third of the vagina.

Answer 175

Answer: B The female internal genitalia includes the fallopian tubes, uterus, and upper one third of the vagina Reference: Linda Constanzo (p.449)

Question 176

Which of the following functions of the Sertoli cells mediates negative feedback control of follicle-stimulating hormone (FSH) secretion? A. Synthesis of inhibin B. Synthesis of testosterone C. Aromatization of testosterone D. Maintenance of the blood–testes barrier

Answer 176

Answer: A Inhibin is produced by the Sertoli cells of the testes when they are stimulated by follicle-stimulating hormone (FSH). Inhibin then inhibits further secretion of FSH by negative feedback on the anterior pituitary. The Leydig cells synthesize testosterone. Testosterone is aromatized in the ovaries. Reference: BRS Physiology p.258

Question 177

What forms the elements of ruptured primary follicles? A. Theca cells B. Corpus Albicans C. Corpus Luteum D. Fibroblasts

Answer 177

Answer: C The residual elements of the ruptured primary follicle form the corpus luteum. The corpus luteum is composed primarily of granulosa cells but also of theca cells, capillaries, and fibroblasts. The corpus luteum synthesizes and secretes steroid hormones, which are necessary for implantation and maintenance of the zygote should fertilization occur. Reference: Linda Constanzo (p.449)

Question 178

How many days does it take for the the entire period of spermatogenesis, from spermatogonia to spermatozoa? A. 28 days B. 14 days C. 74 days D. 84 days

Answer 178

Answer: C Spermatogenesis, from spermatogonia to spermatozoa, takes about 74 days. Reference: Guyton and Hall p.997

Question 179

Which step in steroid hormone biosynthesis, if inhibited, blocks the production of all androgenic compounds but does not block the production of glucocorticoids? A. Cholesterol → pregnenolone B. Progesterone → 11-deoxycorticosterone C. 17-Hydroxypregnenolone → dehydroepiandrosterone D. Testosterone → estradiol

Answer 179

Answer: C The conversion of 17-hydroxypregnenolone to dehydroepiandrosterone (as well as the conversion of 17-hydroxyprogesterone to androstenedione) is catalyzed by 17,20-lyase. If this process is inhibited, synthesis of androgens is stopped. Reference: BRS Physiology(p.258)

Question 180

A female athlete who took testosterone-like steroids for several months stopped having normal menstrual cycles. What is the best explanation for this observation? A. Testosterone stimulates inhibin production from the corpus luteum B. Testosterone binds to receptors in the endometrium, resulting in the failure of the endometrium to develop during the normal cycle C. Testosterone binds to receptors in the anterior pituitary that stimulate the secretion of FSH and LH D. Testosterone inhibits the hypothalamic secretion of GnRH and the pituitary secretion of LH and FSH

Answer 180

Answer: D The cells of the anterior pituitary that secrete LH and FSH, along with the cells of the hypothalamus that secrete GnRH, are inhibited by both estrogen and testosterone. The steroids taken by the woman caused sufficient inhibition to result in cessation of the monthly menstrual cycle. Reference: Guyton And Hall Physiology Review p. 229

Question 181

After complition of first Meiotic division of each primary spermatocytes, how many secondary spermatocytes will be produced? A.1 B. 2 C. 3 D. 4

Answer 181

Answer: A 2 spermatocytes is produced because during the first meiotic prophase, the hallmark of sexual reproduction involving chromosomal reduplication, synapsis, crosssing over and homologous recombination take place. Reference: Guyton 12th edition pg 1793

Question 182

How many polar bodies are produced after Meiosis II? A. 1 B. 2 C. 3 D. 4

Answer 182

Answer: C One of the daughter cells from the 2nd meiotic division is relegated to becoming a second polar body. The 1st polar body may also divide during the second meiotic division. Reference: Guyton 12th edition pg 1793

Question 183

What is the analogous of Leydig cells? A. Thecal cells B. Granulosa cells C. Both a and b. D.Oocyte

Answer 183

Answer: B Thecal cells are analogous to testicular Leydig cels, they reside outside the epithelial nurse cells, Thecal cells do not express high levels of 17b-HSD. Reference: Berne and Levy pg. 771

Question 184

The major product of Thecal cells is? A. Androgens B. Androstenedione C. Both a & b D. Estrogen and Progesterone

Answer 184

Answer: B A Klinefelter syndrome is due to a meiotic non disjunction which leads to a 47 xxy genotype that leads to testicular atrophy. Reference: Berne and Levy pg. 771

Question 185

What is the effect of Estradiol-17B on the liver? A. It improves circulating lipoprotein B. It increases adipose tissue C. It stimulats intestinal Calcium absorption D. It decreases HDL levels

Answer 185

Answer: A It increases expressions of Low Density Lipoprotein receptor without increase clearance of rich Low Density Lipoprotein by the lver and increases the High Density lipoprotien. Reference: Guyton 12th edition pg 1827-1828

Question 186

Semen is composed of: 10%? 60%? 30%? A. Sperm from Vas deferens, fluid from Seminal vesicles, fluid from prostate gland B. fluid from seminal vesicles, sprem form vas deferens, fluid from prostate gland C. Fructose, citirc acid, phospate D. calcium, clotting enzyme, sprem from Vas deferens

Answer 186

Answer: A 10% Sperm from Vas Deferens, 60 % fluid from Seminal vesicle and 30% fluidfrom Prostate gland Reference: Guyton 12th edition pg 1796

Question 187

The diffusion of Calcium ions inward through the oocyte membrane and cause multiple cortical granules to be released by Exocytosis from the oocyte into the previtelline space may result to? A. Almost never does more than one sperm enter the oocyte during fertilization B. Decrease testosterone C. Increase the reabsorption of sodium on the distal tubulesof the kidneys D. Increase thickness of the skin that can contribute to the development of acne.

Answer 187

Answer: A The diffusion of Calcium ions inward through the oocyte membrane and cause multiple cortical granules to be released by Exocytosis from the oocyte into the previtelline space. These granules contain substances that permeate all portions of the zona pellucida and prevent binding of additional sperm and they even cause any sperm that have already begun to bind to fall off. Thus, almost never does more than one sperm enter the oocyte during fertilization Reference: Berne and Levy pg. 771

Question 188

Which of the following does not affect the spermatogenesis? A. Testosterone B. LH C. FSH D. Inhibin

Answer 188

Answer: D Inhibin is a glycoprotein, it has a negative feedback effect on the anterior pituitary gland which causes decrease secretion of FSH. Testosterone is for growth and division of spermatogonia, Luteinizing hormone stimulates secretion of testosterone, Follicle stimulating hormone converts of Spermatids of sperm and Growth hormone for metabolism of the testis. Reference: Guyton 12th edition pg 1809

Question 189

What hormones are increase during ovulation phase? A. Prolactin B. FH and LH C. Progesterone D. None of the above

Answer 189

Answer: B These hormones are secreted by the anterior pituitary gland, it stimulates ovulation, formation of corpus luteum and synthesis of estrogen and progesterone. Reference: Guyton 12th edition pg. 1823-1825

Question 190

When dies the formation of seminiferous tubules and sertoli cells happen? A. 6-7 weeks B. 8-9 weeks C. 9 weeks D. 10 weeks

Answer 190

Answer: A At 8-9 weeks Leydig cells are formed, at 9 weeks definitive tests is present and secretion of testosterone is established. Reference: Guyton 12th edition pg. 1802-1804

Question 191

After the early proliferative phase of growth, the mass of granulosa cells secretes a follicular fluid that contains a high concentration of ___________? A. Progesterone B. Estrogen C. Prolactin D. Both A & B

Answer 191

Answer: B Granulosa cells secretes a follicular fluid that contains a high concentration of ESTROGEN after early proliferative phase fo growth. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1040

Question 192

Which of the following is not an effect of Estrogen? A. Decrease Protein Deposition B. Increase Body Metabolism and Fat Deposition. C. Osteoporosis of the Bones due to its deficiency in old age D. Development of the stromal tissues of the breasts

Answer 192

Answer: A Estrogen causes slightly INCREASEprotein deposition. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1045

Question 193

These are all functions of progesterone EXCEPT: A. Promotes increased secretion by the mucosal lining of the fallopian tubes. B. Promotes development of the lobules and alveoli of the breasts C. Increases the frequency and intensity of uterine contractions D. Promotes Secretory Changes in the Uterus

Answer 193

Answer: C Progesterone DECREASES the frequency and intensity of uterine contractions. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1046

Question 194

All of which are effects of estrogen loss in the function of the body, EXCEPT: A. “hot flushes” B. Psychic sensations of dyspnea C. Irritability D. Insomnia

Answer 194

Answer: D Loss of estrogen DOESN'T cause insomnia. Reference: Vander's Human Physiology The Mechanisms of Body Function, 13th ed., p. 1051

Question 195

All but one of the follwing is TRUE of Female Orgasm A. Local sexual stimulation reaches maximum intensity local sensations B. It is supported by appropriate psychic conditioning signals from cerebellum C. Analogous to emission and ejaculation in the male help D. It promote fertilization of the ovum

Answer 195

Answer: B Female Orgasm is supported by appropriate psychic conditioning signals from the CEREBRUM. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1052

Question 196

The following are factors that increase uterine contractility, EXCEPT: A. Decrease Ratio of Estrogens to Progesterone B. Stretch of the Uterine Musculature C. Stretch or Irritation of the Cervix D. Effect of Fetal Hormones on the Uterus

Answer 196

Answer: A INCREASE Ratio of Estrogens to Progesterone causes increase uterine contractility. Reference: Guyton and Hall Medical Physiology, 13th ed, p1064

Question 197

Eclampsia is an extreme degree of preeclampsia characterized the following, EXCEPT: A. Clonic seizures in the mother B. Sometimes followed by coma C. Increase kidney output D. Malfunction of the liver

Answer 197

Answer: C Eclampsia causes decrease kidney output. Reference: Guyton and Hall Medical Physiology, 13th ed, p1064

Question 198

TRUE or FALSE: The most common cause of female sterility is failure to ovulate. A.TRUE B. FALSE

Answer 198

Answer: A The most common cause of feamle sterility is failure to ovulate Reference: Guyton and Hall Medical Physiology, 13th ed, p.1053

Question 199

TRUE or FALSE: Simply thinking sexual thoughts or even dreaming that the act of intercourse is being performed can initiate the male act, culminating in ejaculation. A.TRUE B. FALSE

Answer 199

Answer: A Simply thinking sexual thoughts or even dreaming that the act of intercourse is being performed can initiate the male act, culminating in ejaculation. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1026

Question 200

All but one of the follwing is an effect of Human Chorinonic Gonadotropin (HCG)? A. Persistence of corpus luteum and prolongs menstruation. B. Causes the corpus luteum to secrete even larger quantities of its sex hormones for the next few months. C. Stimulates the Male Fetal Testes to Produce Testosterone. D. Maintains the decidual nature of the uterine endometrium.

Answer 200

Answer: D HCG causes persistence of corpus luteum and PREVENTS menstruation. Reference: Guyton and Hall Medical Physiology, 13th ed, p.1060