Nas 150 Chapter 9 Endocrine System

Front 1

Function of the Endocrine System

Back 1

Is one of the two control systems of the human body. It acts to cordinate and direct the activitties of the body's cells

Front 2

Amino Acid-Based Molecules (Non-Steroids)

Back 2

Includes proteins, peptides and amines

Front 3

Steroids

Back 3

Made from cholesterol- include sex hormones and those hormones produced by the adrenal cortex

Front 4

Phospholipids

Back 4

Prostaglandins- "local hormones" made from highly active lipids found in the cell's plasma membrane

Front 5

Mechanisms of Hormone Action

Back 5

Although the hormones circulate through the blood to all organs of the body, they exert their effects on the target cells only.

Front 6

Target Cell

Back 6

Has specific protein receptors on its plasma membrane or in its interior to which that hormone can attach. Only when this binding occurs can the hormone influence the workings of a cell.

Front 7

Major Endocrine Systems in the Head

Back 7

Pituitary (Master Gland)
Pineal Gland
Hypothalamus

Front 8

Major Endocrine Systems in the Neck

Back 8

Thyroid
Parathyroid Glands

Front 9

Major Endocrine Organs in the Chest

Back 9

Thymus

Front 10

Major Endocrine Organs in the Abdomen

Back 10

Adrenal Gland
Pancreas
Ovaries

Front 11

Major Endocrine Organs in the Scrotum

Back 11

Testes

Front 12

Hormones Trigger Changes in Cells via what two mechanisms

Back 12

Steroid Hormone Action
&
Amino Acid-Based (Non-Steroid Hormone) Action

Front 13

Steroid Hormone Action

Back 13

Direct Gene Activation
-Lipid soluble molecule diffuses through the plasma membrane of their target cell and enters the nucleus
-Molecule then binds to specific receptor proteins
-Hormone-receptor complex then binds to specific sites on the cell's DNA
-This activates certain genes to synthesize RNA
-RNA then triggers synthesis of new proteins

Front 14

Amino Acid-Based (Non-Steroid Hormone) Action

Back 14

-A second Messenger System (Amino Acid Based)
-This molecule is unable to enter the target cell and instead binds to receptors situated on the target cell's plasma membrane
-This sets off a series of reactions that activates an enzyme
-This enzyme catalyzes a reaction that produces a second messenger molecule like cyclic AMP, G proteins, calcium ions.
-This oversees additional intracellular changes that promote the typical response of the target cell to the hormone.

Front 15

Function of
Endocrine System

Back 15

-Maintains homeostasis by releasing chemicals called "hormones" that control prolonged or continuous processes such as growth, developement, reproduction and metabolism
-Hormones are chemical substances that act as messengers. They are secreted by cells into the extracellular fluids and regulate the metabolic activity of other cells in the body.