hormonal control in humans

• what is the main reproductive hormone in men

  testosterone
• what is the main reproductive hormone in women

  oestrogen
• how many stages are there in the menstrual cycle

  4
• what is stage 1 of the menstrual cycle

  menstruation starts- uterus lining breaks down for about 4 days
• what is stage 2 of the menstrual cycle

  uterus lining builds up again- day 4-14 into a thick spongy layer full of blood vessels, ready to receive the fertilised egg
• what is stage 3 of the menstrual cycle

  an egg develops and is released- from the ovary at day 14 (ovulation)
• what is stage 4 of the menstrual cycle

  the wall is maintained- from day 14-28, if no fertilised egg has landed on the uterus wall, the lining starts to break down and the cycle restarts
• what are the 4 hormones during the menstrual cycle

  1. FSH
  2. oestrogen
  3. LH
  4. progesterone
• where are the 4 hormones produced-

  • FSH- pituitary gland
  • oestrogen- ovaries
  • LH- pituitary gland
  • progesterone- ovaries
• what do the 4 hormones do-

  • FSH- causes egg to mature in a structure called follicle, stimulates ovaries to produce oestrogen
  • oestrogen- causes lining to grown, stimulates release of LH and inhibits release of FSH
  • LH- stimulates the release of an egg
  • progesterone- maintains lining in second half of cycle, when levels fall, the lining breaks down and inhibits the release of LH and FSH