Quiz 2 Lecture Material

Question 1

Sex determination in mammals

Answer 1

XX or XY

Question 2

What gene determines male or female

Answer 2

Sex-determining region Y
SRY gene
y linked- only found on Y chromosome

Question 3

XXY

Answer 3

Klinefelter’s syndrome
sterile- testicular hypoplasia

Question 4

XO

Answer 4

Turner’s syndrome
sterile- inactive ovaries

Question 5

Why is only one X expressed in females

Answer 5

one is inactivated to prevent too many proteins

Question 6

The sequence of development of the reproductive system

Answer 6

Indifferent stage
development of gonads
development of the tubular reproductive tract
development of external genitalia
sexual development of the brain

Question 7

Indifferent stage

Answer 7

bipotential gonad
has the potential to be either

Question 8

Gonads by default will go towards the

Answer 8

ovary
female tract
female genitalia

Question 9

genital ridge

Answer 9

structure in the embryo that develops into gonads

Question 10

Wilms Tumor gene

Answer 10

suppresses steroidogenic factor 1 to avoid the development of steroidogenic cells instead of supporting cells

Question 11

Steroidogenic factor

Answer 11

when not inhibited will create steroidogenic cells
- cells that produce gametes and hormones

Question 12

What causes the development of gonads

Answer 12

migration of primordial germ cells from the yolk sac to the genital ridge

Question 13

How does SRY gene differentiate the gonad

Answer 13

SRY leads to the Soc9 transcription factor that codes for Sertoli cell formation
– makes testis

Question 14

The job of Sertoli cells

Answer 14

support of spermatogenesis- making sperm cells

Question 15

Development of tubular male reproductive tract

Answer 15

Testes produce testosterone which stimulates the growth of the wolfian ducts
and Antimullerian hormone which inhibits the growth of the mullerian (female) tract

Question 16

Development of tubular female reproductive tract

Answer 16

default
- no testosterone or antimullerian= female

Question 17

Cryptorchidism is when

Answer 17

one or two testes stay tucked up near the abdomen
if they stay there too long then the testes will degrade- sterile

Question 18

What ligament connects the testicle to the scrotum and shrinks so the testicles can descend

Answer 18

gubernaculum ligament

Question 19

Three genitalia origins

Answer 19

genitial tubercle
genitial fold
genitial swelling

Question 20

From the genitial tubercle what develops

Answer 20

penis
clit

Question 21

From the genitial fold what develops

Answer 21

prepuce
vulva (inner)

Question 22

From the genitial swelling, what develops

Answer 22

scrotum
vulva (outer)

Question 23

Male genital differentiation is reliant on what hormone

Answer 23

5 alpha Dihydrotestosterone

Question 24

How is 5 alpha dihydrotestosterone made

Answer 24

from testosterone
enzyme used is 5 alpha-reductase

Question 25

Why do we get free martins in cows

Answer 25

the male and female fetus share a placenta which allows testosterone and antimullerian hormone to flow to the female- often making her infertile

Question 26

by default the brain will go to which side

Answer 26

female

Question 27

What makes the brain go to the male side

Answer 27

testosterone is small enough to pass the blood-brain barrier turned into estrogen by aromatase in the brain estrogen leads to male

Question 28

what makes the brain develop into the female side

Answer 28

Alpha-fetoprotein binds to estrogen it can't go into the brain because it is too big

Question 29

where is alpha-fetoprotein produced

Answer 29

in the fetal liver

Question 30

What happens in testicular feminization

Answer 30

Genotype- XY Gonads- Testis Repro Hormones- Testosterone and antimullerian hormone but no testosterone receptors tubular tract- no male or female tract External genitalia- female Brain- Male

Question 31

What happens in androgenital Syndrome

Answer 31

Genotype- XX Gonads- ovaries Reproductive Hormones- testosterone Tubular tract- male and female external genitalia- male brains- male

Question 32

what happens in Persistent Mullerian Duct

Answer 32

Genotype- XY Gonads- Testes Reproductive Hormones- Testosterone but no Anitmullerian hormone tubular tract- male and female external genitalia- male brain- male

Question 33

What happens in 'penis at twelve' syndrome

Answer 33

Genotype- XY gonads- testes reproductive hormone- testosterone and Antimullerian hormone but no alpha reductase enzyme activity tubular tract- male external genitalia- female at birth; male at puberty brain- male

Question 34

Male anatomy exocrine function

Answer 34

spermatozoa

Question 35

Male anatomy endocrine function

Answer 35

testosterone (Leydig cells)

Question 36

How is sperm produced/ moved

Answer 36

produced in the lobule of the testis moves to tubules rete tubules at center efferent tubules at head of epidydimis to the body of epididymis then tail stored in the tail vas deferens then ejaculated

Question 37

How is sperm made in the lobule

Answer 37

produced by one cell at the edge goes towards the lumen and differentiated complete sperm at lumen goes into rete testis

Question 38

How can a male be fertile for their entire life but females are not

Answer 38

females have a limited number of eggs Males have a cell that makes sperm called type A spermatogonium that will split into two B spermatogonium and one will become the A type to replenish the cycle

Question 39

what do leydig cells do

Answer 39

make testosterone

Question 40

How are the testicles thermoregulated

Answer 40

Scrotum Dartos muscle Cremaster muscle Pampiniform plexus

Question 41

How does the scrotum thermoregulate the testicles

Answer 41

moves the testicles away from the body and contains nerve cells that connect to the brain

Question 42

How does the tunica Dartos muscle thermoregulate testicles

Answer 42

lines the scrotum from inside cold- shrivels to maintain heat hot- relaxes to increase surface area

Question 43

How does the cremaster muscle thermoregulate the testicles

Answer 43

connects the testicle to the inguinal canal brings testicle closer or farther away from the body

Question 44

How does the pampiniform plexus help thermoregulate the testicles

Answer 44

arterial blood is hot when entering the testicles so it is covered by the plexis filled with cooler blood returning cools the arterial blood