The Endocrine

System

oDef: System of glands in various parts of the body that manufacture & secrete hormones into the bloodstream

o hormones = chemical substances; Greek for “to excite”; affect other body cells

o pituitary gland = just below hypothalamus; master gland that controls/turns on other glands in the endocrine system & releases a growth hormone

o underactive pituitary = dwarf

o overactive pituitary = giant

o Thyroid gland = in front, lower part of neck; produces thyroxin, which regulates metabolism

o metabolize = to change food into energy

o hyperthyroidism (too much thyroxin) = thin, nervous, unable to relax

o hypothyroidism (too little thyroxin) = overweight, sluggish

o Parathyroid gland = behind thyroid; regulates calcium metabolism

o Thymus = controls lymph system; affects immune system

o adrenal glands = just above kidneys; release epinephrine & norepinephrine which activate the sympathetic nervous system (prepares body for emergencies & stressful situations)o Adrenal glands also release:o small amounts of sex hormoneo corticoids, which control the salt

balance in your bodyo Pancreas = curved around small intestine &

stomach; produces insulin & regulates blood sugaro diabetes (not enough insulin) = too much

sugar in bloodo hypoglycemia (too much insulin)= low

blood sugar o control both with diet; diabetics

sometimes inject insulin

o Gonads = sex glands that produce sex hormones, make reproduction possible, & responsible for secondary sex characteristics

o pubic & underarm hair, breasts in women, facial hair & deepened voice in men

o Female gonads = ovaries (produce estrogen & progesterone)

o Male gonads = testes (produce testosterone)

Hormonal/Endocrine System-Brief Overview for Primary/Secondary Students: youtube

Gigantism – youtube