development

Question 1

how does PRL affect ovulation

Answer 1

low FSH/LH, no LH surge, low E2, low AVPV stimulation, no ovulation

Question 1

how does PRL affect gonadotropins

Answer 1

reduces responsiveness of LH and FSH

Question 2

is PRL a reliable source of contraception

Answer 2

yes

Question 3

what is the milk ejection reflex

Answer 3

suckling from infant causes oxytocin release from posterior pituitary

Question 4

how does oxytocin contribute to lactation

Answer 4

-oxytocin causes contraction of smooth muscles of myoepithelial cells
-squeezing alveoli forces milk out of nipple
-conditioning can lead to oxytocin release upon seeing/smelling/hearing baby

Question 5

what are the internal reproductive structures of a male

Answer 5

epididymis, vas deferens, seminal vesicles

Question 6

what are the internal reproductive structures of a female

Answer 6

oviduct, uterus, cervix

Question 7

what are the external reproductive structures of a male

Answer 7

penis, scrotum

Question 8

what are the external reproductive structures of a female

Answer 8

vagina, clitoris, labia

Question 9

what is the SRY gene

Answer 9

-sex determining region of Y
-testis-determining factor

Question 10

what is the pseudo-autosomal region involved in

Answer 10

-bone formation => height

Question 11

how can an XX person have testicles

Answer 11

-translocation of Y chromosome to X chromosome

Question 12

what is the DAX-1 gene

Answer 12

dose-sensitive repressor gene (repressing SRY)

Question 13

what is X-inactivation

Answer 13

-when there are two X chromosomes, one X chromosome gets “shut down” in each cell
-event is random
-results in formation of Barr bodies

Question 14

are pseudo-autosomal regions always transcribed

Answer 14

yes

Question 15

what are the characteristics for klinefelter syndrome

Answer 15

-XXY genotype (or XXXY, XXXXY)
-some dose-dependent gene in the pseudo-autosomal region of X chromosome
eg: DAX-1
-DAX-1 leads to hypogonadism
-altered fertility
-leads to increased height (SHOX)

Question 16

how does klinefelter syndrome occur

Answer 16

-during puberty, rise in gonadotropins do not cause normal growth of Leydig or Sertoli cells
-Leydig cells become abnormal: decreased testosterone and increased gonadotropins
-increased estrogen:androgen ratio

Question 17

how does XO genotype (turner syndrome) affect follicular development

Answer 17

ovaries don’t form correctly with only 1 X chromosome so no follicular development

Question 18

how does XO genotype (turner syndrome) affect estradiol production

Answer 18

no granulosa cells, no E2

Question 19

how does XO genotype (turner syndrome) affect secondary sex characteristics

Answer 19

none because they come from E2

Question 20

how does XO genotype (turner syndrome) affect height

Answer 20

decreased height