1. Excretory System
‘Urine Good Hands’

2. https://www.youtube.com/watch?v= 0YHwLStC8E8

3. Key Structures
Kidneys
Ureter
Bladder
Urethra

4. Creating Waste
During metabolic processes, the body produces waste that must be eliminated.

5. Creating Waste
A significant source of this waste is the breakdown of proteins.
We need protein in our diet as it is a source of amino acids, which the body uses for building and repair.

6. Creating Waste
Amino acids that are not used up are broken down in the liver and the amino groups are converted into ammonia.
BUT ammonia is extremely toxic.

7. Creating Waste
In the liver ammonia is quickly combined with carbon dioxide to produce urea, which is less toxic.

8. Creating Waste
Urea is dissolved in blood and is carried to the kidneys where it is excreted in the urine.

9. Kidneys
The kidneys are located in the back of the upper abdomen on either side of the spinal column.

10. Kidneys Kidneys are the filters that removed waste from the blood.
They can hold up to 24% of the body’s blood at ay given time.

11. Kidneys Urine formation depends on four processes: i) Filtration
ii) Reabsorption
iii) Secretion
iv) Excretion

12. Filtration Filtration: Renal arteries bring blood to the kidneys
Blood travels to a nephron which is surrounded by capillaries
Fluids to be processed enter Bowman’s Capsule from blood

14. Reabsorption Reabsorption Occurs in the “Loop of Henle”
119 ml returned to the blood, 1 ml becomes urine (urine = 95% water, 5% urea, salts, etc.)

16. Secretion
Secretion
Some other excess substances are actively transferred into the nephron for elimination

18. Excretion
Excretion:
Urine is carried by ureters to the bladder for storage (200 ml = first warning, 400 ml = second warning, 600 ml = too late!)
When it is time, urinary sphincter opens & urine enters urethra & exits body

19. https://www.youtube.com/watch?v= 2_7Q1xQ-NWU

20. Kidneys Proper functioning kidneys are essential for health.
Kidney disfunction affects other body systems, and kidneys are affected when other body systems break down.