endocrine system

• Endocrine system


  Network of glands across the body that secrete chemical messages called hormones
• Endocrine system


  • Uses blood vessels to transport hormones around the body to a specific target cell
  • Different hormones produce different effects
• Hormone


  Chemical message secreted by the endocrine system that excites (stimulates) a particular part of the body
• Hypothalamus


  • Connected to the pituitary gland and responsible for stimulating or controlling the release of hormones from the pituitary gland
  • The control system which regulates the endocrine system

  
• Pituitary gland


  • The master gland because the hormones it releases control and stimulate the release of hormones from other glands in the endocrine system
  • Divided into anterior (front) and posterior (rear) lobes which release different hormones
• Anterior pituitary lobe


  Releases adrenocortical trophic hormone (ACTH) which stimulates the adrenal cortex and the release of cortisol
• Posterior pituitary lobe


  Releases oxytocin which is responsible for uterus contractions during childbirth
• Pineal gland


  Releases melatonin, which is responsible for important biological rhythms, including the sleep-wake cycle
• Thyroid gland


  Releases thyroxine which is responsible for regulating metabolism
• Adrenal gland


  • Divided into adrenal medulla and adrenal cortex
  • Adrenal medulla releases adrenaline and noradrenaline which play a key role in 'fight or flight'
  • Adrenal cortex releases cortisol which stimulates the release of glucose while suppressing the immune system
• Testes


  Release androgens, including the main hormone testosterone, which is responsible for the development of male sex characteristics during puberty and muscle growth
• Ovaries


  Release oestrogen which controls the regulation of the female reproductive system, including the menstrual cycle and pregnancy
• Gland


  • Hypothalamus
  • Pituitary Gland
  • Pineal Gland
  • Thyroid Gland
  • Adrenal Gland
  • Testes
  • Ovaries

  
• Main hormone released


  • Hypothalamus - Stimulates and controls the release of hormones from the pituitary gland
  • Anterior pituitary - Adrenocortical trophic hormone (ACTH)
  • Posterior pituitary - Oxytocin
  • Pineal gland - Melatonin
  • Thyroid gland - Thyroxine
  • Adrenal medulla - Adrenaline & noradrenaline
  • Adrenal cortex - Cortisol
  • Testes - Testosterone
  • Ovaries - Oestrogen
• Effect


  • Anterior pituitary - Stimulates the adrenal cortex and the release of cortisol during the stress response
  • Posterior pituitary - Responsible for uterus contractions during childbirth
  • Pineal gland - Responsible for important biological rhythms, including the sleep-wake cycle
  • Thyroid gland - Responsible for regulating metabolism
  • Adrenal medulla - The key hormones in the fight or flight response
  • Adrenal cortex - Stimulates the release of glucose to provide the body with energy, while suppressing the immune system
  • Testes - Responsible for the development of male sex characteristics during puberty, while also promoting muscle growth
  • Ovaries - Controls the regulation of the female reproductive system, including the menstrual cycle and pregnancy