Lesson 4 The Endocrine Glands

• Endocrine glands - glands that secrete hormones into the bloodstream
• Homeostasis - the tendency of the body to maintain a balance among internal physiological conditions
• major endocrine glands: pituitary, parathyroid, thyroid, thymus, adrenal, pancreatic glands, and gonads
• Pituitary gland - "master gland"
• two parts of the pituitary gland - anterior pituitary and posterior pituitary
• Posterior Pituitary - releases hormones oxytocin and vasopressin
• oxytocin - involved in childbirth and nursing, the "love hormone"
• vasopressin - indirectly controls blood pressure
• anterior pituitary - includes control of the timing and amount of body growth
• Parathyroid glands - produces the hormone called parathormone
• thyroid gland - produces thyroxine, regulates metabolism
• the thymus - the "childhood gland", produces the blood cells that make antibodies
• Pancreas - secretes two hormones which control the level of blood sugar and glucose on the bloodstream
• Adrenal glands - located above the kidneys, secrete epinephrine(adrenaline) and norepinephrine(noradrenaline)
• Epinephrine(adrenaline) - increases heart rate and blood pressure, increases blood flow to muscles
• Norepinephrine(noradrenaline) - stimulates the release of steroids which cause the liver to release stored sugar
• The Gonads - produce the sperm and egg cells for reproduction, and secrete hormones called androgens(male) and estrogens(female)