1. Kidneys and Excretory System

2. How Urination works http://health.howstuffworks.com/adam- 200032.htmhttp://health.howstuffworks.com/adam- 200032.htm

3. Excretion The process of excretion involves the removal of metabolic waste. If wastes build up in the body, they become toxic. There are 4 main organs that work to remove waste from the body.

4. Excretion con’t 1.The skin - removes waste heat, some urea, and other materials found in sweat 2. The lungs - removes C02 3. The large intestine - removes solid wastes of the digestive process 4. The kidneys - removes urea, uric acid, extra water and salts

5. Anterior View of the Urinary System

6. Posterior View of the Urinary System

7. Questions page 380 1-3 1.List 3 main functions of the kidney. a. Eliminates wastes b. regulation of water balance - Also regulation of pH - Also regulates blood pressure and is involved in the production of red blood cells.

8. Questions page 380 1-3 con’t 2. What is deamination and why is it an important process? -Deamination is the removal of the amino groups from a protein (organic compound) -Amino groups = 2 H + 1 N

9. Questions page 380 1-3 con’t 2 con’t -Deamination occurs in the liver -Important to convert excess amino acids into carbohydrates and other nutrient compounds

10. Questions page 380 1-3 con’t 3. How does the formation of urea prevent poisoning? - Deamination produces ammonia, a water soluble gas. - Ammonia is extremely toxic and cannot be stored in the body. - The liver combines two molecules of ammonia with carbon dioxide to form urea. - Urea is 1000 times less toxic than ammonia. -Animals can store urea for short periods of time in their bodies -Permits the controlled excretion of urine

11. Questions page 383 4-5 4. State the function… Bowman’s capsule: The filtration of water and dissolved solutes happens as blood is forced from the glomerulus to the Bowmen’s capsule Proximal tubule: Selective reabsorption of nutrients from filtrates back into the blood Loop of Henle: Reabsorption of water and salt Distal Tubule: secretion of substances from the blood to the urine Collecting duct: Urine formation

12. The urethra is the only part of the urinary system that differs between males and females. It is longer in males.

13. Questions page 319 4-5 con’t 5. List and describe the 3 processes involved in urine formation. a.Filtration – involves the movement of fluids from the Bowman’s capsule to the glomerulus. b.Reabsorption – involves the movement of fluids from the nephron into the interstitial fluid and eventually the capillary net. c.Secretion – involves the selective transport of fluids from the capillary net into the nephron.