Endocrine system

• The endocrine system is a network of glands secreting chemical messages called hormones. Instead of using nerves to transmit information this system uses blood vessels. This is a faster system.
• The hypothalamus stimulates and controls the release of hormones from the pituitary gland therefore regulating the endocrine system.
• The pituitary gland is known as the master gland because the hormones released by the pituitary gland stimulate the release of other hormones from the glands in the endocrine system
• Endocrine system works slower than the nervous system
• Endocrine system uses hormones to transmit information more slowly with longer lasting effects
• Endocrine’s chemical messages travel through the bloodstream
• Pineal Gland releases melatonin responsible for important biological cycles
• Thyroid gland releases thyroxin and is responsible for regulating metabolism
• Adrenal gland releases adrenaline and noradrenaline responsible for fight or flight
• Adrenal gland releases adrenal cortex releasing cortisol stimulating the release of energy which suppresses immune system
• Ovaries release oestrogen controlling the regulation of female reproductive system
• Testes release testosterone responsible for the development of male sex characteristics whilst promoting muscle growth
• The amygdala senses stress and sends a sensory input with emotions to the hypathamulus which communicates with the sympathetic nervous system
• • The hypothalamus prepares the body for action response
  • The sympathetic nervous system is activated
  • Adrenaline is released from the adrenal gland
• • A person enters stressful situation
  • Amygdala sends distress signal to hypothalamus
  • The hypothalamus activates the sympathomedulary pathway running to the adrenal medulla and sympathetic nervous system
  • The sms stimulates adrenal medulla
  • Adrenal medulla releases adrenaline
  • Adrenaline causes a number of psychological changes
• Direct Effects of Adrenaline

  Increased heart rate, respiration and sweating

  Increases rate of blood flow and pressure

  Diverts blood away from skin, kidney and digestive system

  Increases blood flow to the brain and spinal cord
• General effects of Adrenaline

  Prepares body for fight of flight

  Increased blood supply to skeletal muscles for physical action

  Increased oxygen to brain for rapid response planning