2.2 hormonal control of reproduction

• What is the role of the hypothalamus in hormonal control of reproduction?

  It secretes releaser hormones.
• What does the pituitary gland regulate?

  Temperature, water concentration, and growth.
• What hormone does the hypothalamus secrete at puberty?

  A releaser hormone targeting the pituitary gland.
• What hormones does the pituitary gland release in response to the releaser hormone?

  FSH and LH or ICSH.
• What is the effect of FSH in men?

  It stimulates sperm production.
• What does LH do in women?

  It triggers the start of the menstrual cycle.
• What are the male and female versions of ICSH?

  ICSH is the male version of LH.
• What triggers the physical and psychological changes of puberty?

  Oestrogen and testosterone detected by receptors.
• What do negative feedback cycles ensure in males and females?

  Constant sperm production and regular ovulation.
• What are the two main functions of the testes?

  Sperm production and testosterone production.
• What does FSH promote in the testes?

  Sperm production in the seminiferous tubules.
• What does ICSH promote in the testes?

  Testosterone production in interstitial cells.
• How does testosterone affect sperm production?

  It stimulates sperm production and gland activation.
• What happens when testosterone levels increase?

  It inhibits FSH and ICSH production.
• What is the menstrual cycle's approximate duration?

  About 28 days.
• What marks the start of the menstrual cycle?

  The first day of menstruation.
• What are the two phases of the menstrual cycle?

  Follicular phase and luteal phase.
• What does FSH do during the follicular phase?

  Stimulates follicle development and oestrogen production.
• What effect does oestrogen have on the endometrium?

  It stimulates proliferation and prepares for implantation.
• What does peak oestrogen levels trigger?

  A surge in LH secretion from the pituitary.
• What is ovulation?

  The release of an egg from a follicle.
• When does ovulation typically occur in the menstrual cycle?

  Around day 14.
• What happens during the luteal phase?

  The empty follicle develops into the corpus luteum.
• What hormone does the corpus luteum secrete?

  Progesterone.
• What does progesterone promote in the endometrium?

  Further development and vascularisation.
• What happens if fertilisation occurs?

  The corpus luteum continues producing progesterone.
• What triggers the start of menstruation?

  Falling levels of progesterone.
• What does low FSH level cause at the end of the cycle?

  It suppresses further follicle development.
• What does low LH level cause at the end of the cycle?

  Degeneration of the corpus luteum.
• What happens to oestrogen levels at the end of the cycle?

  They decrease, prompting FSH secretion.
• What hormone does the implanted embryo produce if fertilisation occurs?

  A hormone that maintains progesterone production.
• What are the key hormones involved in the menstrual cycle?

  • FSH (Follicle Stimulating Hormone)
  • LH (Luteinising Hormone)
  • Oestrogen
  • Progesterone
• What are the phases of the menstrual cycle?

  1. Follicular phase

  • Development of follicles
  • Ovulation

  1. Luteal phase

  • Development of corpus luteum
• What are the effects of testosterone in males?

  • Stimulates sperm production
  • Activates prostate gland and seminal vesicles
  • Involved in negative feedback mechanism
• What are the effects of oestrogen in females?

  • Stimulates endometrium proliferation
  • Affects cervical mucus consistency
  • Triggers LH surge for ovulation
• What is the negative feedback mechanism of testosterone?

  • High testosterone inhibits FSH and ICSH
  • Low testosterone increases FSH and ICSH
• What is the role of progesterone in the menstrual cycle?

  • Promotes endometrium development
  • Inhibits FSH and LH secretion
• What hormones are produced by the pituitary gland that affect the ovary?

  LH and FSH
• What does FSH stimulate in the ovary?

  Follicle to grow
• What triggers ovulation?

  LH surge