AIM- Intro. to the Endocrine System,

What is the endocrine system, and what does it do?

-A system of glands that produce and release hormones

-Uses hormones to travel through the bloodstream to deliver messages to organs and tissues

-maintains homeostasis

What are hormones and what do they do?

-Chemicals made by endocrine glands

-travel in blood stream to deliver messages

-control important functions: Growth, metabolism, blood sugar, reproduction, and mood

What does the hypothalamus do, and where is it.

-tells other glands when to release hormones

-helps regulate body heat

-releases hormones like GnRH to start the menstrual cycle

-in the mid-front portion of the brain, superior to the pituitary gland

Where is the pituitary gland and what does it do?

-in mid-front brain, inferior to the hypothalamus

-controls other endocrine glands

-resleases hormones such as GH, TSH, and ACTH

Where is the pineal gland and what does it do?

-in the center of the brain, dorsal to the pituitary and hypothalamus

-produces melatonin and responds to light/dark

Where is the thyroid gland and what does it do?

-Butterfly-shaped gland in the front of the neck

-controls body’s metabolism and how the body uses energy

-supports normal growth and brain development(especially during childhood)

Where are the adrenal glands and what do they do?

-”hats” for kidneys

-respond to stress and regulate important body functions

-produce adrenalin(epinephrine) and cortisol to help in stressful situations

-releases aldosterone to help regulate salt and water in the body

Where is the pancreas and what does it do?

-behind the stomach(long and flat gland)

-produces insulin which helps cells absorb glucose(lowers blood sugar)

-produces glucagon by releasing glucose from the liver(raises blood pressure)

-works to keep blood levels stable

Where are the ovaries and what do they do?

-two small, oval-shaped glands on each side of the uterus

-release progesterone and estrogen, hold eggs

Where are the testes and what do they do?

-two oval shaped glands located in the scrotum

-release testosterone

negative vs positive feedback

positive feedback; response increases the effect of the stimulus(ex. in birth oxytocin)

negative feedback; response decreases the effect of the stimulus

What are the processes of the HPA Axis

-stress response

Hypothalamus(notices stress and sends signal)→ pituitary(passes the message to adrenal glands and releases ACTH)→ adrenal glands(release cortisol)

-Negative feedback; once cortisol levels are high, the hypothalamus tells everyone to stop