1.2 Flashcards
Each Graafian follicle is cells surrounding an…
Oocyte
The ovaries contains many …
Graafian follicles at different stages of development
The first menstrual cycle is called the..
Menarche
Each month a few follicles start to develop but usually only one..
Oocyte is released
The first part of the cycle, a primary follicle starts to develop, the follicle cells grow and divide.
On about day 14 the follicle bursts releasing the oocyte surrounded by a few follicle cells known as:
Ovulation
The oocyte enters the oviduct and is moved towards the
Uterus
The ruptured follicle continues to grow and forms a structure called the:
Corpus luteum
The corpus luteum produces
Hormones
If the woman becomes pregnant the corpus luteum remains in the ovary inhibiting
Further menstrual cycles
If the woman doesn’t become pregnant, the corpus luteum degenerates and
Another cycle begins
1)The menstrual cycle starts when the pituitary gland secretes:
Follicle stimulating hormone
2)FSH travels in the blood to the ovary where it causes a
Follicle to develop
3)as the follicle grows and develops, it releases
Oestrogen
4) oestrogen stimulated the thickening of the endometrium it also:
Inhibits secretion of FSH and stimulates the production of LH from the pituitary gland
5) by about day 11 the oestrogen concentration in the blood is very high because of the size of the developing follicle
This high level of oestrogen causes the:
LH stored in the pituitary gland to be released in a surge and it also causes a surge in FSH
6) the surge in LH brings about ovulation. The mature follicle…
Bursts releasing the oocyte into the oviduct
7)LH stimulates the ruptured follicle to develop into a corpus luteum which continues to secrete some oestrogen, but now secretes large amounts of progesterone which :
Inhibits FSH and LH
Stimulates the growth of blood vessels in the endometrium
8) As LH is now inhibited, the corpus luteum starts to degenerate and produces
Less progesterone
9) the fall in progesterone means that FSH is no longer inhibited, so FSH is released again and..
A new cycle starts
10) the fall in progesterone and oestrogen leads to
Menstruation
Outer layer of the endometrium is shed and lost from the body
Base temperature increases by
1 degree at ovulation time
After ovulation the endometrium becomes
Thicker and highly vascularised
The endometrium thickens under the influence of
Oestrogen
Menstruation is initiated by falling levels of
Oestrogen and progesterone as the corpus luteum degenerates
