reproductive physiology

Question 1

what is the sex HPG axis

Answer 1

hypothalamus release GnRH –> ant pit releases LH and FSH –> testes/ ovaries –> testosterone and oestrogen reduce GnRH from hypothalamus

Question 2

what does FSH do in females

Answer 2

causes growth of follicles + secretion of oestrogen and oestradiol

Question 3

what does LH do in females

Answer 3

after ovulation, causes corpus luteum to produce progestogen and prepares for pregnancy

Question 4

what does FSH do in males

Answer 4

causes sperm production

Question 5

what does LH do in males

Answer 5

causes testes to secrete testosterone

Question 6

what activates the GnRH receptor in the hypothalamus

Answer 6

kisspeptin

Question 7

what type of hormone is GnRH

Answer 7

neuropeptide

Question 8

what is different about the release of GnRH in females vs males

Answer 8

females is pulsatile manner!! males is steady

Question 9

what does low frequency pulsation in the hypothalamus cause in females

Answer 9

low frequency = FSH = oestrogen. oestrogen then becomes concentrated and increases pulsation

Question 10

what does high frequency pulsation in the hypothalamus cause in females

Answer 10

high frequency = LH = progestogen - increased progesterone reduces pulsation and completes negative feedback loop

Question 11

what happens to GnRH in the onset of puberty in females

Answer 11

GnRH pulsation

Question 12

what does GnRH pulsation control in females

Answer 12

menstrual cycle

Question 13

when is the follicular phase of the menstrual cycle

Answer 13

day 1-14 (pre-ovulation)

Question 14

what hormone increases in the follicular phase and what is released from the developing follicles

Answer 14

FSH increases and follicles release oestrogen

Question 15

what does concentrating oestrogen cause just before ovulation

Answer 15

LH surge

Question 16

when does ovulation begin

Answer 16

34-36 hours after LH surge

Question 17

what happens to a woman’s body temp during ovulation

Answer 17

increases by 1C

Question 18

what happens in the luteal phase

Answer 18

preparation for pregnancy: formation of corpus luteum from empty follicle which secretes progesterone

Question 19

what is the longest a menstrual cycle can last and still be normal

Answer 19

35 days

Question 20

what is a follicle

Answer 20

an oocyte surrounded by antrum (fluid), theca cells and granulosa cells

Question 21

what does growth of a follicle mean

Answer 21

increased number of fluid and surrounding cells - NOT increased egg numbers

Question 22

what does progesterone do to the follicle

Answer 22

breaks down the antrum so the oocyte is released (ovulation)

Question 23

how do theca and granulosa cells produce oestrogen

Answer 23

theca cells (activated by LH) covert cholesterol –> androgen and granulosa cells (activated by FSH) then convert androgen to oestrogen

Question 24

what enzyme converts androgens to oestrogen in granulosa cells

Answer 24

aromatase

Question 25

when do follicles start to grow

Answer 25

puberty

Question 26

what is a dominant follicle

Answer 26

one that can cope with decreased FSH

Question 27

what cells form luteal cells after ovulation

Answer 27

granulosa and theca cells

Question 28

what does the corpus luteum secrete in the luteal phase

Answer 28

progesterone

Question 29

what happens do the corpus luteum if the egg is not fertilised

Answer 29

stops secreting progesterone and dies

Question 30

in a fertilised egg what does the embryo secrete

Answer 30

HCG

Question 31

what secretes oestrogens

Answer 31

follicles and adrenal cortex

Question 32

what effect does oestrogen have on the womb (2)

Answer 32

increases thickness of vaginal and uterus wall for implantation, decreases viscocity of mucous

Question 33

what effect does oestrogen have on LH and pH (3)

Answer 33

regulates LH surge, reduces vaginal LH and reduces lactic acid pH

Question 34

what effect does progesterone have on the womb (4)

Answer 34

maintains endometrium thickness, makes the mucous thick again, relaxes smooth muscle in pregnancy, increases body temp

Question 35

where is sperm made

Answer 35

testes

Question 36

what hormone in males decreases FSH to reduce spermogenesis

Answer 36

inhibin

Question 37

what cells produce testosterone and what hormone are they influenced by

Answer 37

Leydig cells under LH control

Question 38

what does testosterone travel bound to

Answer 38

SHBG and albumin

Question 39

what is testosterone converted into

Answer 39

dihydrotestosterone and oestradiol

Question 40

what happens on day one of the mentrual cycle

Answer 40

bleeding

Question 41

what does oligomenorrhea mean

Answer 41

long cycles >35 days

Question 42

what does amenorrhea mean

Answer 42

absent periods

Question 43

what does menorrhagia mean

Answer 43

heavy periods

Question 44

what does dysmenorrhea mean

Answer 44

painful periods

Question 45

what is primary hypogonadism

Answer 45

problem in the ovaries/ testes and high LH/FSH = hypergonadotrophic hypogonadism

Question 46

what can cause primary hypogonadism

Answer 46

premature ovarian failure, klinefelter's syndrome, chemo

Question 47

what is secondary hypogonadism

Answer 47

problem with the pituitary/ hypothalamus - hypogonadotrophic hypogonadism

Question 48

what can cause secondary hypogonadism

Answer 48

kallman syndrome, head injuries, anorexia