1. JH-KEADLE
The Excretory System

2. Organs of the Excretory System
sweat glands
lungs

3. The Excretory System Functions
The excretory system collects wastes produced by cells and removes them from the body
Urea (waste from breakdown of protein)
helps maintain homeostasis by maintaining water balance and eliminating liquid waste

4. Organs of the Excretory System
kidneys – major organs of the excretory system that filters blood and eliminates urea, excess water, and other wastes

5. Organs of the Excretory System

6. Organs of the Excretory System
ureters – two narrow tubes that urine flows through to get to the bladder

7. Organs of the Excretory System
urinary bladder – sac-like, muscular organ that stores urine

8. Organs of the Excretory System
urethra – tube that urine travels to leave the body

9. The Filtering Process
Every drop of blood in your body passes through the kidneys and is filtered 300 times a day
nephrons – tiny structures
that filter blood in the
kidneys

10. Filtering Out Waste
After entering the kidneys, blood flows through smaller and smaller arteries
The blood eventually reaches a cluster of capillaries called nephrons
In the nephron, urea, glucose, other chemicals, and some water move out of the blood and into the nephron

11. Filtering Out Waste Blood cells and proteins stay in the capillaries
Glucose, water, and small amounts of other substances are reabsorbed into the blood stream
Urea and other wastes stay in the nephrons

12. Filtering Out Waste The liquid left in the tube is urine
The urine moves down the ureters and into the bladder
When the bladder is full, you feel the urge to urinate

14. Filtering Summary 1. both wastes and needed materials are
filtered out of the blood
2. the needed material is returned to the
blood
3. the waste is eliminated in the urine

15. Analyzing Urine Some medical problems can be found by testing urine
Glucose – diabetes
Protein – kidney failure
Drug residue – drug abuse

16. Other Organs of Excretion
There are other organs in our body that can excrete substances
Lungs – carbon dioxide and water
Skin – sweat, water, some chemicals
Liver – breaks down molecules, recycles hemoglobin and turns it into bile

18. Body systems that work with the respiratory system;
Depends on the circulatory system to move the waste from the cell and deliver it to the kidneys, the respiratory system to remove carbon dioxide and the integumentary system to remove salts as sweat

19. Comparing Cells to Body
What cell organelle helps to break down waste?
lysosomes
What cell organelle packages waste?
golgi body