Multi Systems Physiology Practice Test With Answer And Explanation

Item: 1 of S
QIO: 3134
- ,•
~
Mark -<J
P~v•ous
[:::>
N@xt Labl
"'I
lues
~ ·
Notes
~
Calculator

. 1
A newly married couple is frustrat ed wit h their inabilit y to conceive a child. They make an appointment at a fertility clini
•2
year-old man is diagnosed with a low sperm count wit h no apparent cause. Repeated attempts at in v itro fertilizat ion ar
·3 their next clinic appointment, the man inquires about an alternative method for improving fertility t hat he discovered on
• 4 physician has never used clomiphene citrate for male infertility before and decides to research its mode of act ion .
·5
If the patient were to take clomiphene citrate, which of the following hormone receptors would most likely be affected?

A. Estrogen
B. Gonadotropin-releasing hormone
C. Inhibin
D. Luteinizing hormone
E. Testosterone




8
Lode.

, Item: 1 of S ~ ,• Mark <::J [:::> ""I ~· ~'j
QID: 3134 J.. Previous Next LAb faiUI~S Notes Calculator

1
•2
•3
•4 The correct a ns wer is A. 3 6°/o chose t h is.
Clomiphene cit rat e is a select ive est rogen receptor modulat or (SERM) t hat works as an ant iest rogen at t he level of t he
. 5
reducing t he feedback inhibit ion effect of est roge n. This leads to increased secret ion of gonadotropin-releasing hormon
hypothalamus, which ult imately leads t o increased secretion of follicle-st imulat ing hormone (FSH) and luteinizing horm
pi tuitary. LH increases test osterone production in the Leydig cells, which in some men results in increased fertility. Clom
hypogonadism is an off-label use, but it has been proven t o be a more desirable t reat ment than test osterone replacem
Clomiphene is more commonly used for fema le infe rtility, particularl y in anovulation seen in polycystic ovari an syndrom
Follicle-stimulating hormone Selective estrogen receptor modulator Antiestrogen Luteinizing hormone Off-label use Gonadotropin-releasing hormone Anovulation Polycystic o

Estrogen Estrogen receptor Testosterone Clomifene Hypogonadism Androgen replacement therapy Hormone Pituitary gland Leydig cell Female infertility Infertility Enzyme in

Citric acid


B is not correct. 28% chose this .
GnRH is key to the fe rtility benefit of clomiphene cit rat e, but estrogen signaling is most direct ly affected . Secretion of G
hypothalamus increases as a result of reduced feedback inhibit ion by est rogen .
Estrogen Hypothalamus Clomifene Gonadotropin-releasing hormone Enzyme inhibitor Citric acid Fertility


C is not correct. 8 °/o chose this .
I nhibin is produced by t he Sertoli cells in response to follicle -st imulat ing (FSH). It acts as negative feedback at the ante
secret ion, thereby decreasing spermatogenesis.
Spermatogenesis Anterior pituitary Activin and inhibin Sertoli cell Pituitary gland Negative feedback Follicle-stimulating hormone Anatomical terms of location

D is not correct. 18% c hose this .
Although lut einizing hormone act s on the Leydig cells of t he t estes to st imulat e t estost erone synthesis, which is key t o
fertilit y, clomiphene cit rat e acts most direct ly on est rogen.
Luteinizing hormone Testosterone Estrogen Clomifene Testicle Hormone Leydig cell Citric acid


E is not correct. 10°/o chose this.
Test ost erone is t he end product of clomiphene cit rate, but estrogen signaling is most direct ly affected by cl omiphene ci
Estrogen Testosterone Clomifene Citric acid




8
Lock

, Item: 1 of S ~ ,• Mark <::J [:::> ""I ~· ~'j
QID: 3134 J.. Previous Next faiUI~S
LAb Notes Calculator

1
•2 Bottom Line:
•3
Clomiphene cit rat e is a selective est rogen receptor modulat or (SERM) t hat acts as an ant iest rogen, which leads t o inc
•4 GnRH and ult imately to increased test osterone, which can improve some men's fertil it y.
. 5 Selective estrogen receptor modulator Antiestrogen Estrogen Clomifene Estrogen receptor Testosterone Gonadotropin-releasing hormone Receptor (biochemistry) Citric acid




141;fil·1i•J
FIRS T AID FACTS
for year:[ 2017
.
•j .




Diagnosing disorders Testosterone LH Diagnosis
of sex hormones f f Defective androgen receptor
t l Testosterone-secreting tumor, exo
steroids
f Hypergonadotrophic hypogonadis
l Hypogonadotropic hypogonadism




Selective estrogen receptor modulators
Clomiphene Antagonist at estrogen receptors in hypothalamus. Prevents normal feedback inhibition
f release of Ll l and FSII from pituita ry, which stimulates ovulation. Used to treat inf
to anovulation (eg, PCOS). lay cause hot Rashes, ovarian enlargement, multiple sim
pregnancies, visua l disturbances.

8
Lock