• As well as adrenaline, insulin, testosterone, progesterone and oestrogen, the following hormones are also of great importance in humans:
  • ADH?(antidiuretic hormone)
  • FSH?(follicle-stimulating hormone)
  • LH?(luteinising hormone)

   

ADH and its role in osmoregulation

• If the water content of the blood falls below a certain level:
  • The blood is?too concentrated
  • Receptors detect this and stimulate the pituitary gland to release?more?ADH
  • This causes the collecting ducts of the nephrons to become?more permeable?to water
  • This leads to?more water being reabsorbed?from the collecting ducts
  • The kidneys produce a?smaller volume of urine?that is?more concentrated?(contains?less water)

   

• If the?water content of the blood rises above a certain level:
  • The blood is?too dilute
  • Receptors detect this and stimulate the pituitary gland to release?less?ADH
  • This causes the collecting ducts of the nephrons to become?less permeable?to water
  • This leads to?less water being reabsorbed?from the collecting ducts
  • The kidneys produce a?larger volume of urine?that is?less concentrated?(contains?more water)

   

Hormonal control of the menstrual cycle

• Four hormones control the events that occur during the?menstrual cycle.?These are:
  • Oestrogen
  • Progesterone
  • FSH (follicle-stimulating hormone)
  • LH (luteinising hormone)

   

• Oestrogen?and?progesterone?are involved in?maintaining the uterus lining
  • Oestrogen is produced by the ovaries and progesterone is produced by an empty egg follicle called the corpus luteum

   

• The other two hormones are produced by the?pituitary gland?in the?brain:
  • FSH?causes the?maturation of an egg in the ovary
  • LH?stimulates the?release of the egg

   

The roles of FSH and LH

• FSH?is released by the?pituitary gland?and causes an?egg to?start maturing?in the ovary
• It also?stimulates the ovaries?to start releasing?oestrogen
• The?pituitary gland?is stimulated to release?LH?when?oestrogen?levels have reached their peak
• LH?causes?ovulation to occur?and also?stimulates the ovary?to produce?progesterone

Changes in the levels of the pituitary hormones FSH and LH in the blood during the menstrual cycle

Other Important Hormones in the Human Body Table