2. Endocrine System Overview
target cell
hormone
bloodstream
receptor
not a target cell
Glands: Major organs of the endocrine system
Glands make hormones
Hormones: chemical signals
Hormones move through bloodstream
Hormone binds to cell receptor
Target cells produce proteins

3. There are steroid hormones and nonsteroid hormones
Steroid hormones enter into the cell.
Nonsteroid hormones do not enter the cell.
Steroid hormone
Non-steroid hormone
Steroid hormone diffuses through the cell membrane
Steroid hormone binds to a receptor within the cell.
The hormone and receptor enter the nucleus and bind to DNA
Steroid hormone causes DNA to make proteins.
Nonsteroid hormone binds to receptor on the cell membrane.
Receptor stimulates a second messenger with in the cell.
Second messenger starts a series of chemical reactions in the cytoplasm.
Second messenger reactions activate enzymes.
receptor
second messenger
receptor
nucleus
Chemical reactions
DNA
proteins
activated enzymes

4. All the below create hormones
Major Glands
All the below create hormones
Hypothalamus
Stimulates the pituitary gland to release hormones
Controls growth, reproduction, body temp
Pituitary gland
Controls cell growth and [H2O] in blood
Stimulates other glands
Thyroid gland
Regulates metabolism, growth, development
Thymus
Allows WBCs to mature to fight infection
Adrenal Glands
Controls “fight or flight” response
Increases breathing, alertness, blood pressure
Pancreas
Controls glucose level in blood
Insulin, glucagon
Gonads: influence sexual development
Testes (males): testosterone
Ovaries (females): Estrogen, progesterone
HYPOTHALAMUS
PITUITARY
THYROID
THYMUS
ADRENAL GLANDS
PANCREAS
FEMALE GONADS :OVARIES
MALE GONADS : TESTES

5. Releasing hormones stimulate other glands to produce hormones
Allow glands to communicate with one another
Are used in temperature regulation
cold
hormone A
(TRH)
hormone B
(TSH)
hormone C
(Thyroxine)

6. Hormonal imbalances can cause severe illness
Abnormal hormone levels affect homeostasis.
Hormonal imbalances might be treated with surgery or medicine.
Steroids, a pituitary tumor, or some prescription drugs can make the pituitary overactive and indirectly cause problems.

7. Hypothalamus
Pituitary gland
Thyroid
Thymus
Adrenal glands
Pancreas
Ovaries
Testes