A&P: The endocrine system

what is the endocrine system?

complex message-and-control system that integrates many body functions

composed of endocrine glands that release hormones [such as epinephrine, norepinephrine, and insulin] directly into the bloodstream

what are the endocrine glands and their functions/hormones?

• adrenal: epinephrine, norepinephrine, cortisol → stress, fight-or-flight reaction

• ovaries: estrogen and others → regulate sexual function, characteristics, and reproduction

• pancreas: insulin, glucagon, and others → regulation of glucose metabolism and more

• parathyroid: parathyroid hormone → regulates serum calcium

• pituitary: multiple hormones produced → controls all other endocrine glands

• testes: testosterone and others → regulate sexual function, characteristics, and reproduction

• thyroid: thryoxine and others → regulates metabolism

what are hormones?

chemical messengers that can have a stimulating or inhibiting effect on the body’s organs and systems

• scared → stimulation of adrenal gland → epinephrine and norepinephrine released → brain reduces amount of stimulation to adrenal gland

what are hormonal feedback loops?

feedback loops help keep the body’s systems in balance, as excess of deficiencies in hormones cause various diseases

• stimulus → endocrine gland stimulated → hormone secreted into bloodstream → hormone interacts with target tissue → effect produced → effect becomes new stimulus