At puberty, body starts releasing sex hormones that trigger off secondary sexual characteristics such as facial hair and breasts and can cause eggs to mature
men
main reproductive hormone is testosterone
produced by testes stimulating sperm production
women
main reproductive hormone is oestrogen
produced by ovaries
can bring about physical changes and is involved in menstruation cycle
Menstrual cycle
Day 1-4 = lining of uterus breaks down
Day 4-14 = lining of the uterus builds up
Day 14 = egg released ovulation
Day 14-28 = lining of the uterus maintained
if no fertilised egg has landed on the uterus wall by day 28, the spongy lining starts to break down and the whole cycle starts again
Menstrual cycle is controlled by 4 hormones
FSH (follicle stimulating hormone)
produced by the pituitary gland
causes an egg to mature in one of the ovaries, in a structure called a follicle
stimulates the ovaries to produce oestrogen
Menstrual cycle is controlled by 4 hormones
2. oestrogen
produced in ovaries
causes lining of uterus to grow
stimulates release of LH and inhibits release of FSH
Menstrual cycle is controlled by 4 hormones
3. LH luteinising hormone
produced by pituitary gland
stimulates release of an egg at day 14 (ovulation)
Menstrual cycle is controlled by 4 hormones
4. Progesterone
produced in ovaries by remains of the follicle after ovulation
maintains lining of the uterus during the second half of the cycle when the level of progesterone falls, the lining breaks down
