Hormones

• Hormones


  Help to regulate metabolic processes in the body
• Hormones


  Secreted into the blood through endocrine glands
• Hormones


  Travel in the blood to organs where they take effect
• Hormone Reference Chart


  • Gland
  • Hormone
  • Target organs
  • Effect
• Adrenal gland


  • Secretes adrenalin
  • Prepares body for action - 'fight or flight'
• Ovary


  • Secretes oestrogen
  • Controls puberty and the menstrual cycle in females
  • Stimulates production of LH and suppresses the production of FSH in the pituitary gland
• Ovary


  • Secretes progesterone
  • Maintains the lining of the womb
  • Suppresses FSH production in the pituitary gland
• Pancreas


  • Secretes insulin
  • Controls blood sugar levels
• Pituitary gland


  • Secretes anti-diuretic hormone (ADH)
  • Controls blood water level by triggering uptake of water in kidneys
• Pituitary gland


  • Secretes follicle stimulating hormone (FSH)
  • Triggers egg ripening and oestrogen production in ovaries
• Pituitary gland


  • Secretes luteinising hormone (LH)
  • Triggers egg release and progesterone production in ovaries
• Testes


  • Secrete testosterone
  • Controls male reproductive organs
• This video explains more about Hormones and the effects they have
• The menstrual cycle


  1. Egg ripens in the ovaries - stimulated by FSH

  2. Womb lining builds-up - stimulated by Oestrogen

  3. Egg is released - stimulated by the LH (about day 14)

  4. Maintenance of uterus lining - stimulated by progesterone

  5. Uterus lining breaks down - caused by low levels of oestrogen and progesterone

  6. Blood and tissue loss (menstruation)
• Hormones involved in the menstrual cycle


  • Oestrogen
  • Progesterone
  • FSH (Follicle stimulating hormone)
  • LH (Luteinising hormone)
• Hormones


  Responsible for controlling many parts of the reproduction process
• Aspects of reproduction controlled by hormones


  • Development of sex organs
  • Production of sex cells
  • Controlling pregnancy and birth
• Testosterone


  Controls changes in male body at puberty
• Oestrogen


  Controls changes in female body at puberty
• Secondary sexual characteristics


  Changes occurring in male and female bodies at puberty
• Sperm


  Sex cells produced in males
• Eggs


  Sex cells produced in females
• After puberty, sperm are produced continuously but in the female one egg is usually released about once a month
• Oestrogen levels are high in the first half of the cycle


  Prepares the wall of the uterus to receive a fertilised egg
• Oestrogen levels are high in the first half of the cycle


  Triggers the release of an egg (ovulation)
• Progesterone is high in the second half of the cycle


  Further repairs the wall of the uterus and stops it breaking down
• Pituitary gland


  Releases hormones that control the production of oestrogen and progesterone
• Increasing fertility


  1. Fertility drug containing hormones similar to FSH stimulates production of eggs

  2. Eggs removed and fertilised outside body, then embryo put back in uterus (IVF)
• Decreasing fertility


  Oral contraceptives containing hormones prevent pituitary gland releasing FSH, so ovary does not produce eggs
• The pituitary gland is located at the base of the brain, just below the hypothalamus.
• The hypothalamus is the master gland that controls other endocrine glands