4.4 - The Endocrine System & Homeostasis

Question 1

What is the endocrine system?

Answer 1

• It is a chemical signaling pathway of hormones that conveys info between glands.
• ideal for slower, long term adjustments
• releases hormones through the blood stream

Gland(s): specialized tissues that release hormones to organs

Question 2

What is the nervous system?

4.4

Answer 2

• ideal for fast, short term adjustments
• operates bu sending signals through neurons

Question 3

What are hormones?

4.4

Answer 3

• chemical regulators made in one part of the body that affects a different area
• they are stored in glands
• ## they are released through the bloodand can reach all parts of the body

Question 4

What are target cells?

4.4

Answer 4

• have receptors for hormones to initiate a response

Question 5

What is the pituitary gland?

4.4

Answer 5

• sometimes called the “master” gland
• some of the hormones that it releases can control other glands
• under the control of the hypothalamus (this is the link between the endocrine system and the nervous system)

Question 6

What are steroid hormones?

Answer 6

• are lipids
• they are derived from cholesterol
• usually affect gene expression
• can pass through the membrane

Question 7

What are protein hormones?

Answer 7

• typically require a special membrane receptor
• made of amino acids (ex. insulin, adrenaline, etc)
• affects cell activity
• water souble; can’t pass directly through the membrane
• protein hormones activate the release of a secondary messenger inside the cell to carry out its function b/c it cannot enter the cell
• only small amounts of hormones are needed to acitvate a response. The receptor usually amplifies it