1. The Excretory System

2. Part of Homeostasis Helps to maintain homeostasis Removes metabolic wastes If not removed, these wastes could be harmful

3. Different Waste Products Your body produces many waste products Some examples are salt, carbon, dioxide, urea Urea: toxic compound produced when amino acids are used for energy Wastes leave body through excretion

4. The Skin The skin is an organ of excretion The skin excretes water and urea in sweat

5. The Lung The lungs are organs of excretion They expel the waste product carbon dioxide.

6. The Liver Converts amino acids into useful compounds Nitrogen wastes are created in the process The nitrogen becomes urea, which is expelled out of the body

7. The Kidneys Remove waste products Maintain blood pH Regulate water content and volume of the blood

9. Nephrons Converts amino acids into useful compounds Nitrogen wastes are created in the process The nitrogen becomes urea, which is expelled out of the body

11. Reabsorption Some materials (water, amino acids, etc.) are reabsorbed into the blood This primarily takes after filtration in Bowman’s capsule in the loop of Henle

12. Secretion Secretion is the process in which some molecules move from the blood to the filtrate This takes place after filtration Molecules secreted into the filtrate include hydrogen and other light compounds

13. Urine Formation Urine: material that is not reabsorbed into the blood Urine includes urea, salt, water,, and other substances. Urine is located in the loop of Henle Nephron ➝ Collecting Duct ➝ Ureter ➝ Urinary Bladder ➝ Urethra

14. Summary

15. Bibliography Miller, Kenneth R., and Joseph S. Levine. "The Excretory System." Prentice Hall Biology. N.p.: Person Education, Inc., 2007. 985-989. "Treatment Methods For Kidney Failure: Kidney Transplantation." National Kidney and Urologic Diseases Information Clearing House. 9 Jan. 2009 <http://www.kidney.niddk.nih.gov/kudiseases/pubs/transplant/>. "Your Kidneys and How They Work." National Kidney and Urologic Diseases Information Clearinghouse. Aug. 2007. 11 Jan. 2009 <http://www.kidney.niddk.nih.gov/Kudiseases/pubs/yourkidneys/>.