The Endocrine System

Purpose: Produce hormones that maintain homeostasis by regulating & coordinating the functions of virtually all organ systems Glands Organs that secrete hormones Hypothalamus, pituitary, thyroid, parathyroid, pancreas, kidney, adrenal, ovaries / testes, etc.

Endocrine glands YouTube “Human Body – Endocrine System – Kids Animation…”

Hormones Chemical messengers  released by cells, transported through the body and have affect on other cells Example - blood water levels are low, pituitary releases ADH (Anti-diuretic Hormone) into bloodstream, ADH transported to kidneys, stimulates water re-absorption! Other examples – table 2, pg 175

“Fight or Flight” Response A startling or fearful event triggers a strong reaction from both the nervous and endocrine systems (preparing the body for defense or escape) Sympathetic nerves stimulates: increased heart rate diversion of blood to muscles dilation of pupils adrenal gland

The End!!! Adrenal Gland secretes adrenaline which stimulates: Increased heart rate Increased blood pressure Perspiration Increased muscle tension *This response is short in duration – Parasympathetic nerves bring body back to homeostasis (harmful if extended… stress) The End!!!