endocrine system

• Endocrine glands


  Produce and secrete hormones, chemical substances that regulate the activity of cells or organs in the body
• Major glands of the endocrine system

  • Pituitary gland
  • Adrenal glands
  • Reproductive organs (ovaries and testes)
• Endocrine system regulation

  1. Signal sent from hypothalamus to pituitary gland

  2. Pituitary secretes 'stimulating hormone'

  3. Stimulating hormone signals target gland

  4. Target gland secretes hormone

  5. Hypothalamus and pituitary shut down secretion as hormone levels rise
• Hormones

  Chemicals that circulate in the bloodstream and are carried to target sites throughout the body
• Target cells


  Cells that have receptors for a particular hormone and can be influenced by it
• Timing of hormone release and levels are critical for normal functioning
• Too much or too little hormone at the wrong time can result in dysfunction of bodily systems
• Pituitary gland


  Produces hormones that influence the release of hormones from other glands, regulating many body functions
• The pituitary gland is controlled by the hypothalamus
• High levels of hormones produced in other endocrine glands can stop the hypothalamus and pituitary releasing more of their own hormones
• Hormones produced by the pituitary gland

  • ACTH
  • LH
  • FSH
  • Oxytocin
• Adrenal glands


  Sit on top of the kidneys, made up of an outer adrenal cortex and inner adrenal medulla
• Hormones produced by the adrenal glands

  • Cortisol (adrenal cortex)
  • Aldosterone (adrenal cortex)
  • Adrenaline (adrenal medulla)
  • Noradrenaline (adrenal medulla)
• Cortisol

  Regulates or supports a variety of important bodily functions including cardiovascular and anti-inflammatory functions
• Aldosterone

  Responsible for maintaining blood volume and blood pressure
• Adrenaline and noradrenaline


  Prepare the body for fight or flight response