Menstrual Cycle

• What should you be able to describe by the end of the video on hormones in human reproduction?


  The roles of hormones in human reproduction and the menstrual cycle
• What is the endocrine system responsible for?


  The release of hormones by glands into the bloodstream
• What hormone do the testes produce in men?


  Testosterone
• What does testosterone stimulate in men?


  The production of sperm in the testes
• What hormone do the ovaries produce in women?


  Estrogen
• What happens to eggs in the ovaries once puberty begins?


  They start to mature and are released every 28 days
• What is the term for the release of an egg from the ovary?

  Ovulation
• What occurs in the uterus in preparation for ovulation?


  The lining becomes thick and spongy
• What happens if the egg is fertilized?

  It can implant into the uterus wall and develop into a baby
• What happens if the egg does not get fertilized?


  Both the egg and the uterus lining are released as a period
• What are the four key hormones involved in the menstrual cycle?

  • Follicle Stimulating Hormone (FSH)
  • Luteinizing Hormone (LH)
  • Estrogen
  • Progesterone
• What does Follicle Stimulating Hormone (FSH) do?


  It causes an egg to mature in the ovary
• What is the role of Luteinizing Hormone (LH)?


  It triggers the release of the mature egg during ovulation
• What is the function of estrogen in the menstrual cycle?


  It causes the lining of the uterus to become thick and inhibits FSH production
• What are the two effects of progesterone?


  It prevents the release of FSH and LH and keeps the uterus lining thick
• What happens to progesterone levels if fertilization does not occur?


  The level of progesterone falls
• What is the result of falling progesterone levels?


  The uterus lining and the egg are released, resulting in a period
• How do FSH and estrogen interact in the menstrual cycle?


  • FSH stimulates the maturation of the egg and the production of estrogen.
  • Increased estrogen levels inhibit further FSH production.
• How do LH and progesterone interact in the menstrual cycle?


  • LH triggers ovulation and the release of the egg.
  • After ovulation, progesterone is produced to maintain the uterus lining and inhibit FSH and LH.
• What can you be asked to interpret in an exam regarding reproductive hormones?


  Graphs of hormone levels during the menstrual cycle
• What happens to the level of FSH during the menstrual cycle?


  It rises initially and then falls due to increased estrogen
• What triggers the peak of LH levels in the menstrual cycle?


  The increase in estrogen levels
• What happens to progesterone levels after ovulation?


  Progesterone levels rise
• What occurs if fertilization does not happen after ovulation?


  Progesterone levels fall, leading to menstruation