2.68a)- Excretion

Understand how the kidney carries out its role of excretion 

• Kidney excretes the urea ( contains Nitrogen- toxic and can't be stored)

1. Blood circulates to the liver and amino acids are broken down into urea
2. Urea circulates to the kidneys and is filtered from the blood
3. The urea is added to water to form urine
4. Urine drains down the ureter to collect in the bladder