The Menstrual Cycle

• What is the role of hormones in human reproduction?

  They regulate various processes including the menstrual cycle.
• What system do scientists refer to when discussing hormones released by glands into the bloodstream?

  The endocrine system.
• What hormone do the testes produce in men?

  Testosterone.
• What effect does testosterone have in men?

  It stimulates the testes to produce sperm.
• 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 ovulation?

  Ovulation is the release of an egg from the ovary, occurring approximately every 28 days.
• What happens to the uterus lining in preparation for ovulation?

  The uterus lining becomes thick and spongy.
• What occurs 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, resulting in 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) in the menstrual cycle?

  It triggers ovulation.
• What is the function of estrogen in the menstrual cycle?

  It maintains the uterus lining and inhibits FSH release.
• What are the two effects of progesterone in the menstrual cycle?

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

  Progesterone levels fall, resulting in a period.
• How do FSH and estrogen interact during the menstrual cycle?

  • FSH causes an egg to mature in the ovary.
  • FSH triggers the ovaries to produce estrogen.
  • Increased estrogen inhibits FSH production.
• How do LH and progesterone interact in the menstrual cycle?

  • LH triggers ovulation.
  • After ovulation, the ovary produces progesterone.
  • Progesterone prevents the release of FSH and LH.
• What can be inferred about the relationship between FSH and estrogen levels during the menstrual cycle?

  Increased estrogen levels lead to decreased FSH levels.
• What is the significance of the peak in LH levels during the menstrual cycle?

  It indicates the timing of ovulation.
• What happens to progesterone levels if fertilization occurs?

  Progesterone levels remain high.