The function of the endocrine system

• Hormones are chemical messages released from glands which control or regulate the activity of cells or organs
• Glands secrete hormones directly into the blood stream and a network of glands is called the endocrine system
• Master gland is the pituitary gland, its called this because of the hormones released from the pituitary gland which control the secretions of other endocrine glands
• Pituitary is divided into an anterior and posterrior portion
• Endocrine gland thyroid release thyroxine which regulates the body's metabolic rate and protein synthesis
• Endocrine gland adrenal medulla releases adrenaline and noradrenaline and it takes part in the fight or flight response so increases heart rate and blood flow
• Endocrine gland adrenal cortex releases hormones like glucocorticords which release stored glucose and fats and supresses immune system and the inflammatory response. It also releases mineral corticoids which regulate water balance of the body
• Endocrine gland testes releases androgens, main one testerone which promotes muscle mass and growth and develops male secondary sexual characteristics at puberty
• Endocrine gland ovaries release oestrogens which regulate female reproductive system, menstrual cycle and pregnancy
• Endocrine gland pineal release melatonin and it regulates arousal, biological rhythms and the sleep-wake cycle
• Posterior pituitary releases antidiuretic hormone (ADH) and oxytocin
• Anterior pituitary releases:

  • Adrenocortical trophic hormone (ACTH)
  • Thyroid stimulating hormone (TSH)
  • prolactin
  • Follicle stimulating hormone (FSH)
  • Growth hormone
  • Melanocyte stimulating hormone (MSH)