1. Excretory System
Fluid’s

2. October 13, 2011 You need: Clean paper /pencil Warm Up:
Turn in your book to Chapter What is the excretory system?

3. October 13, 2011 In your book – Chapter 11, section 3
Write out the 3 key concept questions.
Define the 8 key terms

4. Main Function:
Collects waste produced by cells and removes the wastes from the body. (also known as: excretion)

5. Wastes Eliminated: Excess water
Urea – chemicals that come from the break down of proteins
Other wastes

6. The path of the excretory system
Kidneys – filter blood
Ureters – narrow tubes that leading from the kidneys to the bladder
Urinary Bladder-fist sized pouch (muscular sac) that holds about 2 cups of urine
Urethra – exit tube

7. The Kidneys and their Nephrons
Kidneys filter the blood
Nephrons are used to filter wastes from the blood in your kidneys
1. wastes and needed materials, like glucose and water, are taken out of blood
2. needed materials are returned to the blood, wastes are eliminated.

8. Nephrons
After the reabsorption process is complete, the liquid that remains in the tube is called… URINE.
Capillaries
Capillaries
Urea
Urea, water, glucose, and other materials…
water, glucose
Kidney

9. After the reabsorbing process is complete, the liquid that remains in the tube is called… URINE.

10. What happens in the Nephrons?
Materials and wastes go through the tubes
Protein, glucose, most water, and some other materials return to the blood
Wastes and small amounts of water stay and are excreted

11. Pee in a cup? Urine used to determine diseases
Glucose in urine = diabetes
Protein = kidneys not functioning correctly

12. Homeostasis with Excretion
Excretion maintains homeostasis by keeping the body’s internal environment stable and free of harmful levels of chemicals.
Kidneys
Lungs and Skin
Liver

13. Homeostasis Kidneys Regulate amount of water in your body
Hot day – you will sweat a lot, but you don’t drink a lot so you excrete small amounts of urine

14. Homeostasis Lungs and Skin Exhale carbon dioxide and water vapor
Sweat water and urea
Liver
Breaks down wastes before excreting them