1. Excretory System

2. A. Excretory System
Also known as Urinary system

3. Functions a. Removes nitrogenous wastes
Our bodies have many processes they must perform to function and stay alive

4. Leaves cells as ammonia and is converted into urea
Nitrogenous wastes
(Urea), produced by the breakdown of proteins
Leaves cells as ammonia and is converted into urea
Why must nitrogenous waste be excreted?

5. Functions b. Maintain homeostasis of body fluids
Internal stable conditions

6. How does it work?

7. Organs of the excretory system

8. A. Kidneys
Main organs - filter, concentrate, and eliminate wastes from blood

9. Kidneys
a. About the size of a large bar of soap, sit toward the back

10. Kidneys
b. Clean all the blood in the body in about 25 min.

11. B. Aorta
Brings blood from the heart

12. C. Renal arteries
Carry blood into the kidneys

13. D. Renal veins
Carry blood out of the kidneys

14. E. Inferior vena cava
Returns blood to the heart

15. F. Ureters
Tubes that carry urine from the kidneys to the bladder

16. G. Urinary bladder
Muscular bag that stores urine

17. Bladder
Very stretchy!

18. H. Urethra
Tube that releases urine out of the body

19. 3. Other organs A. Lungs – remove CO₂ from the body
B. Skin – wastes are released with sweat through pores

20. Microscopic View of Kidneys

21. A. Nephron
The kidney’s filters, about 1 million per kidney

22. a. Glomerulus
Clump of capillaries, blood pressure forces fluids and wastes out

23. b. Bowman’s capsule
Cup shaped tube that receives the fluids from the glomerulus

24. 5. Urine Leftover fluids after most water and nutrients are reabsorbed
Mostly water, urea, uric acid

25. Urine Color

27. A. Urine Color Blue Urine Most likely from food dyes or medications
Clear Urine
Can mean healthy, too hydrated, type of diabetes
Dark Yellow Urine
Dehydrated, asparagus can turn urine darker color

28. Urine Color Orange Urine
Blackberries, beets, rhubarb or medications, severe dehydration
Light Yellow Urine
Healthy
Green Urine
Most likely from food dyes or medications
Pink or Red Urine
Beets or berries, blood in urine, kidney or bladder infection

29. 6. Healthy Excretory System
A. Personal hygiene – keep the area around the urethra clean of bacteria
B. Drink plenty of water

30. 7. Problems
A. Urinary Tract Infection – overgrowth of bacteria in the urinary tract
Frequent, painful urinations

31. Problems
B. Kidney stones – crystallized clumps of materials and salts in the urine

32. Kidney transplant

33. Aorta
Inferior vena cava
Renal arteries
kidney
Renal veins
ureter
Urinary bladder
urethra