Menstrual Cycle Flashcards
What are the 4 hormones involved in the menstrual cycle?
Follicle Stimulating hormone - FSH
Luteinising Hormone - LH
Oestrogen
Progesterone
Where is FSH found?
pituitary gland
what does FSH do?
causes follicle to develop in the ovary
What does the follicle secrete?
oestrogen
Where is LH found?
pituitary gland
what does LH do?
drop in LH causes corpus luteum to produce progesterone
increase in LH causes pituitary to produce more FSH and ovulation
Where is oestrogen found?
ovary
What does oestrogen do?
thickens lining of the uterus, inhibits FSH so no more follicles mature, stimulates pituitary to produce LH
Where is progesterone found?
ovary, corpus luteum
what does progesterone do?
uterine lining develops and mammary glands prepare for lactation.
If no fertilisation drop in progesterone means menstruation
If fertilisation implantation, placenta forms, corpus luteum remains and keeps producing progesterone
What is negative feedback?
more common, too much of something causes a reduction in its production to bring levels back to normal
Which 2 hormones provide negative feedback to the pituitary?
Oestrogen and Progesterone
What is positive feedback?
less common, as something increases it causes more extreme levels to be produced
When do Oestrogen and progesterone provide positive feedback?
for rapid increase in oestrogen for ovulation
What does LH cause pituitary to produce more of?
FSH
