1. The Excretory System Purpose: To remove waste products from the body
Excess water -- Urea
Salts Digested food
Carbon dioxide -- Old RBCs
Extra amino acids -- Poisons

2. Organs of the Excretory System
Lungs – remove carbon dioxide (CO2). Capillaries release CO2 into the alveoli. The CO2 is then exhaled.
Liver – removes used amino acids.
Filters out old RBCs and poisons
Produces urea (which is later removed by the kidney)

3. More Organs Kidney – Helps remove
urea
salts
water
digested food molecules from the bloodstream.
Wastes mixed together and are known as urine

4. Urine Urine leave the kidney through the ureter
It is stored in the urinary bladder
When bladder is full, the urine is expelled through the urethra