Endocrine System

• Endocrine System

  Works alongside the nervous system to control vital functions in the body through the action of hormones. It works more slowly but has widespread & powerful effects.
• Glands -organs in the body that produce hormones

  Hormones -are secreted in the bloodstream and affect any cell in the body that has a receptor for that particular hormone
• Glands and Hormones 1/2

  • Pituitary -known as the master gland; it controls the release of hormones from all the other endocrine glands in the body, Its controlled by the CNS.
  • Pineal - produces melatonin and is responsible for the sleep wake cycle
• Glands and Hormones 2/2

  • Thyroid - produces thyroxin which regulates the metabolism and controls attention span, energy, fatigue and weight
  • Adrenal -produces adrenaline which is responsible for stress responses (fight or flight)
  • Pancreas - secretes insulin and glucagon which regulates blood sugar levels
  • Gonads - secretes oestrogen and androgens, these play a role in development aggression and sexual drive.
• Endocrine System and ANS-during a stressful event: 1/2

  • stressor perceived by hypothalamus which activates the pituitary gland
  • the sympathetic nervous system is now aroused
  • adrenaline is released from the adrenal medulla into the bloodstream.
  • This delivers the aroused state causing changes in target organs in the body - increased heart rate, dilation of pupils aka fight or flight.
• Endocrine System and ANS during a stressful event: 2/2

  • immediate and automatic - this response happens the instant a threat is perceived.
  • parasympathetic nervous system takes over once the threat has passed. This returns the body to its resting state rest and digest. This acts as a brake and reduces the activities in the body that were increased by the actions of the sympathetic branch.