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Flashcards in MENSTRUAL CYCLE Deck (45)
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1

what are the stages of the menstrual cycle?

follicular phase
ovulation
luteal phase

2

when does the follicular phase occur?

days 1 - 13/14

3

when does ovulation occur?

days 13/14

4

when does the luteal phase occur?

days 14-28

5

what is the primordial follicle?

1 oocyte surrounded by granulosa cells

6

what does the primordial follicle secrete?

oestrogen
progesterone
inhibin

7

what is the primary follicle?

the oocyte grows and is separated from the granulosa cells by the zona pellucida
they contain glycoproteins

8

what is the role of glycoproteins in the primary follicle?

they are used for binding sperm

9

what are pre-antral follicles?

granulosa cells differentiate into theca cells
the 2 cells function together for oestrogen synthesis

10

what are early antral follicles?

the primary oocyte is full-sized
the antrum forms and is filled with fluid from granulosa cells

11

what is the role of gap junctions between granulosa cells and the oocyte in primary follicles?

nutrients and chemical messengers are passed to the oocyte

12

when and how many mature follicles produced?

at the beginning of each menstrual cycle
10-25

13

what happens to non-dominant follicles in the menstrual cycle?

they undergo atresia (die)

14

what is the graafian follicle?

it is the dominant mature follicle
it increases in size and so does the antrum

15

what triggers the first meiotic division of the primary oocyte and what does it produce?

LH surge
secondary oocyte

16

what is ovulation?

the thin walls of the follicle and ovary rupture at the site where they are joined by enzymatic digestion
the secondary oocyte is carried out of the ovary by antral fluid

17

what happens in the follicular phase of the menstrual cycle?

- oocyte in primordial follicle grows and and separates from granulosa cells by zona pellucida (primary follicle)
- granulosa cells differentiate into theca cells (preantral cells)
- the primary oocyte is full size and antrum forms and fills with fluid (early antral cells)
- one primary oocyte becomes dominant and the rest undergo atresia. Primary oocyte undergoes first division to become secondary oocyte
- undergoes ovulation

18

what happens in the luteal phase of the menstrual cycle?

- after ovulation the follicle collapses
- granulosa cells increase in size and becomes the corpus luteum
- if the egg is not fertilised after 10 days it undergoes apoptosis
- this triggers menstruation
- once it collapses it is called corpus albicans

19

what are the phases of uterine changes in the menstrual cyccle?

menstrual phase
proliferative phase
secretory phase

20

when does the menstrual phase of uterine changes occur?

day 1-5

21

when does the proliferative phase of uterine changes occur?

day 5-14

22

when does the secretory phase of uterine changes occur?

day 15-28

23

what happens in the menstrual phase of uterine changes?

withdrawal of progesterone leads to endometrial degeneration - this is the trigger for menstrual flow

24

what happens in the proliferative phase of uterine changes?

oestrogen from granulosa cells and theca cells causes the endometrium to thicken
this stimulates the myometrium
this stimulates progesterone receptor generation in the endometrium

25

what happens in the secretory phase of uterine changes?

progesterone binds with its receptors in the endometrium
endometrium secretes glycogen from glandular epithelium - this provides a hospitable environment which is nourishing to sperm and oocyte
progesterone overrides oestrogen to prevent myometrium contraction and prostaglandin secretion

26

what is the role of glycogen secretions in the uterus during the secretory phase?

it provides a hospitable environment which is nourishing to sperm and oocyte

27

what is the role of progesterone in the uterus during the secretory phase?

it overrides oestrogen to prevent myometrium contraction and prostaglandin secretion

28

what is mucus secretion like when there are high oestrogen levels?

abundant, clear and watery mucus - this is good for sperm movement and implantation

29

what is mucus secretion like when there is progesterone and oestrogen?

thick and sticky
it stops bacteria from entering and offers protection to the implanted egg

30

where is oestrogen produced in the follicular phase of the menstrual cycle?

it is made by granulosa cells