B8.025 - Ovary Histology/Physiology

Question 1

function of the ovary

Answer 1

produce female germ cells, ova

to synthesize and secrete sreroid and peptide hormones

Question 2

what makes up the medulla of the ovary

Answer 2

vasculature
lymphatics
nerves

Question 3

what are components of the cortex of the ovary

Answer 3

follicles containing oocytes at multiple stages of development
corpora lutea at various stages of function and regression

Question 4

stages of folliculogenesis

Answer 4

primordial
primary
preantral
antral
graafian

Question 5

what is folliculogenesis

Answer 5

a growth and development of immature follicles and oocytes to mature follicles and ova capable of undergoing ovulation and fertilization

Question 6

zona pellucida

Answer 6

composed of 4 glycoproteins ZP1-4, produced/secreted by oocyte, has a sperm binding receptor, acrosome reaction occurs here, block to polyspermy, protection for embryo, tranzonal interaction between granulosa and oocyte

Question 7

what happens with the premordial follicle

Answer 7

granulos cells proliferate into multiple layers, Theca differentiates

Question 8

what happens with the antral follicle

Answer 8

antrum forms, first as several small pockets that coalesce into one
follicular fluid forms, theca differentiates into interna/externa
granulosa continues to proliferate
increased estradiol production

Question 9

what happens with graafian follicle

Answer 9

granulosa continues to proliferate, increasing follicle diameter, increasing blood supply, oocyte pushed to one side

Question 10

what happens in ovulation

Answer 10

surge of LH
basement membrane breaksdown, blood vessel penetration, oocyte moves to center of follicle, cumulus expansion, oocyte resumes meiosis, granulosa cell differentiation, enzyme production

Question 11

steps of oocyte resuming meiosis

Answer 11

completion of meiosis 1
1st polar body
oocyte arrests in metaphase 2

Question 12

steps of granulosa cell differentiation

Answer 12

aromatase off
estradiol to progesterone
proliferation stops

Question 13

enzyme production in ovulation

Answer 13

histamine –> hyperemia

PA = breakdown tunica albuginea

Question 14

steps leading up to oocyte release

Answer 14

increasing pressure
proteolytic activity
oocyte release

Question 15

describe the process of establishment of oocyte complement

Answer 15

during development of the ovary the primordial germ cells migrate from yolk sac to gonadal ridge regulated by c kit

Question 16

when in oocyte development does the cycle arrest

Answer 16

prophase 1 of meiosis

Question 17

describe the development of the oocyte complement

Answer 17

1. initially oocytes are organized in nests
2. some oocytes undergo apoptosis
3. individual oocytes with associated granulosa is left (primordial follicle)

Question 18

how is primordial follicle formation regulated

Answer 18

in part by transcription factors, growth factors, meiotic proteins like CAV1. NGF, DMCI

Question 19

when does menopause occur

Answer 19

when oocytes run out

Question 20

what is the biological checkpoint controlling female reproductive potential

Answer 20

primordial follicle entry into the growing pool

Question 21

how long does development of the follicle take

Answer 21

3 phases:
1 - preantral growth: several months (gonadotropin independent)
2 - tonic growth: 2+ months (gonadotropin responsive)
3 - exponential growth - 21 days (gonadotropin dependent)