Reproductive system Flashcards
what is testosterone
produced by the testes – is the main male reproductive hormone and it stimulates sperm production
what is oestrogen
produced by the ovaries – is the main female reproductive hormone.
what happens during the menstrual cycle
- every 28 days, ovulation takes place
- in preparation for this, the uterus lining becomes thick and spongy
- the egg now makes its way down to the uterus
- if sperm is present the egg can be fertilised, if this happens it can implant into the uterus walls and develop into a baby
- if not, both the egg and the uterus lining are released
what is the role of FSH ( Follicle- stimulating hormone)
Causes an egg to mature in an ovary.
Stimulates the ovaries to release oestrogen
what is the role of Oestrogen
- Repairs, thickens and maintains the uterus lining. -
Stimulates the pituitary gland to release LH. - Stops FSH being produced (so that only one egg matures in a cycle)
what is the role of LH (Luteinising hormone)
Triggers ovulation (the release of a mature egg)
Stimulates the release of an egg
what is the role of progesterone
Maintains the lining of the uterus during the middle part of the menstrual cycle and during pregnancy
- inhibits the release of fsh and lh
why doesn’t menstruation happen during pregnancy
the placenta produces progesterone. This maintains the lining of the uterus during pregnancy and means that menstruation does not happen.
what happens on day 1 of the menstruation cycle
uterus lining breaks down for about 4 days
what happens on stage 2 of the menstruation cycle
uterus lining builds up again, from day 4 to 14, into a thick spongy layer full of blood vessels, ready to recieve a fertilised egg
what happens on stage 3 of the mestruation cycle
an egg develops and is released from the ovary at day 14, this is OVULATION
what happens on stage 4 of the menstrual cycle
the wall of the ovary is well maintained for about 14 days, if no fertilised egg has landed on the uterus wall, the spongy lining starts to break down, cycle starts again
how can oestrogen be used as a contraceptive pill
- prevents the release of an egg, inhibits the production of FSH
how can progesterone be used as a contraceptive pill
- stimulates the production of thick mucus which prevents sperm getting through and reaching an egg
benefits of contraceptive pill
- over 99% effective
- can reduce the risk of certain cancers