female urogenital system

Question 1

number of oocytes at puberty

Answer 1

200,000

Question 2

number ovulated

Answer 2

400

Question 3

ovary size

Answer 3

almond

Question 4

cortex contains

Answer 4

germ cells in follicles

Question 5

medulla contains

Answer 5

vessels, nerves and some steroid-secreting cells

Question 6

interstitial tissue between follicles (stroma) contains

Answer 6

corpus luteum
corpus albicans
derived from previously ovulated follicles

Question 7

blood supply

Answer 7

ovarian artery from aorta

drainage to IVC

Question 8

ovary position

Answer 8

intraperitoneal

attached to the posterior aspect of the broad ligament by the mesovarium, through which vessels and nerves enter

Question 9

ovary major functions

Answer 9

cyclic production of haploid gametes

production of hormones to coordinate the body for successful reproduction

Question 10

before birth cell stage

Answer 10

primary oocyte arrested in prophase 1

build up stores of RNA and protein and rest until puberty

Question 11

cell stages at puberty

Answer 11

go through meiosis 1 to make a secondary oocyte, stops at meiosis 2 (cytoplasm doesn’t split evenly, so only one main cell is produced)
other cell becomes first polar body and degenerates

Question 12

after the secondary oocyte is produced

Answer 12

secondary oocyte is arrested in metaphase 2 and then ovulated
meiosis 2 only completed if fertilised, producing another polar body

Question 13

follicle structure

Answer 13

each follicle has an oocyte with one or more layers of specialised cells and their products

Question 14

granulosa cells function

Answer 14

become more cuboidal in development
equivalent to sertoli
production of steroids (estradiol) and LH receptors
has basal lamina around cells (no blood vessels can pass through)

Question 15

zona pellucida function

Answer 15

glycoprotein rich layer around the oocyte, secreted by oocyte and has sperm receptors at fertilisation

Question 16

theca cells function

Answer 16

on outer surface
inner secrete steroids (produce androgen substrate for estradiol production)
outer layer from a capsule, highly vascularised

Question 17

layers around primordial follicle

Answer 17

just early granulosa cells

Question 18

layers around primary follicle

Answer 18

mature granulosa cells with basal lamina

Question 19

layers around secondary follicle

Answer 19

mature granulosa cells and thecal cell layers

Question 20

follicle development depends on

Answer 20

FSH

Question 21

in secondary follicle, granulosa cells are signalled to

Answer 21

secrete fluid between the granulosa layers to produce an antrum (tertiary follicle)

Question 22

dominant pre-ovulatory follicle selected, causing

Answer 22

large antrum to form, separating the granulosum cells into those around the wall and those around the oocyte

Question 23

primordial follicles recruited to start folliculogenesis until

Answer 23

menopause

Question 24

what occurs between the tertiary follicle and the preovulatory follicle

Answer 24

follicle growth
recruitment
selection
dominance

Question 25

mature follicle structure

Answer 25

fluid filled antrum, large | oocyte, pushed to one side surrounded by 2 or 3 layers of granulosum cells (called cumulus oophorus)

Question 26

what its follicular atresia

Answer 26

about 20 follicles mature each month but only 1 is ovulated | rest undergo atresia (hormonal apoptosis)

Question 27

control of menstrual cycle

Answer 27

hypathalamo = pituitary - gonadal axis

Question 28

LH and FSH release

Answer 28

from gonadotrophs in pituitary | controlled by pulses of gonadotrophin releasing hormone (GnRH) from hypothalamus

Question 29

GnRH control

Answer 29

neuronal hormone kisspeptin

Question 30

negative feedback on pituitary and hypothalamus

Answer 30

progesterone oestrogen inhibin (peptide for neg feedback of FSH)

Question 31

two cell two hormone mechanism

Answer 31

thecal and granulosum cells | and FSH and LH both need to be stimulated by GnRH for ovary function

Question 32

action of LH in ovary

Answer 32

acts at LH receptors on theca interna cells to stimulate the production of androgens via cAMP

Question 33

action of FSH in ovary

Answer 33

at FSH receptors on granulosa cells to produce aromatase which converts androgens to estradiol and inhibin

Question 34

phases of the menstrual cycle

Answer 34

follicular phase and luteal phase

Question 35

length of cycle

Answer 35

28 days starts on first day on menstruation length depends on follicle growth and lifespan of corpus luteum

Question 36

follicular phase dominated by

Answer 36

the products of a single dominant follicle

Question 37

luteal phase dominated by

Answer 37

products of the corpus luteum

Question 38

follicular phase - action of estradiol and inhibin

Answer 38

- inhibit FSH release, so select a dominant follicle

Question 39

follicular phase - action of rising estradiol

Answer 39

- estradiol from dominant follicle stimulates the pre ovulatory surge of LH and FSH - sensitises the pituitary to GnRH, causes GnRH to stimulate a surge of LH

Question 40

surge of LH causes

Answer 40

acts on LH receptors of granulosa cells of dominant follicle to cause ovulation and complete the first meiotic division

Question 41

ovulation process

Answer 41

takes 15 min oocyte ruptures out of follicle - induced by LH - through cAMP, promotes production of prostaglandins and plasminogen - collagen breakdown weakens follicle wall - vascular permeability

Question 42

luteal phase - what forms the corpus luteum

Answer 42

remaining granulosa cells and thecal cells from ruptured follicle

Question 43

effect of LH surge on blood vessels

Answer 43

ingrowth of blood vessels through the basal lamina | changes in enzymes so that progesterone dominates

Question 44

progesterone and estradiol production after ovulation

Answer 44

increases for about 7 days | stimulated by slow LH pulses

Question 45

hCG produced if

Answer 45

fertilisation and implantation occur | no hcg = corpus lutetium degenerates

Question 46

luteolysis causes

Answer 46

progesterone and oestrogen levels fall | negative feedback of FSH and LH removed so follicle development stimulated

Question 47

main function of corpus luteum

Answer 47

secrete progesterone

Question 48

function of oviduct

Answer 48

high estradiol at the end of follicular phase and in luteal phase cause muscular activity in the oviduct causes its end to become closely opposed to the site of ovulation, ciliated epithelium wafts the oocytes into the tube secretions from epithelial ells help nourish the oocyte

Question 49

uterus in menstrual cycle

Answer 49

progesterone and oestrogen produce changes in uterine all to prepare for implantation

Question 50

uterus in early phase of cycle

Answer 50

endometrium relatively thin oestrogen causes it to expand and develop sparse and small glands cells develop microvilli and cilia

Question 51

uterus in secretory phase

Answer 51

begins at ovulation | glands become more coiled and endometrium has maximum thickness

Question 52

uterus changes in vasculature

Answer 52

arteries become more extensive and more spiralled through proliferative phase during late secretory, walls become more ischaemic as arteries spasm, under control of prostaglandins to prevent excessive blood loss

Question 53

hormone control of uterus

Answer 53

``` estradiol = proliferation and spiral artery development progesterone = glandular secretion prostaglandins = arterial spasm , uterine muscle spasm ```

Question 54

hormone release pre/post puberty

Answer 54

``` pre = GnrRH fires occasionally, low secretion of LH/FSH post = GnRH neurons fire about every 90 min, pulses of FSH and LH ```

Question 55

what happens at menopause

Answer 55

oocytes = 0 secretion of oestrogen and inhibin reduced lack of negative feedback = FSH and LH increase

Question 56

blood supply to uterus

Answer 56

internal iliac artery and vein