1. Excretion and Metabolic Wastes
No Crap About it!

2. What are Metabolic Wastes?
All cells metabolize sources of energy to keep them ticking over in terms of making energy molecules they can use to do 'work' with, or making structural components for the cell.

3. What are Metabolic Wastes?
This involves breaking down larger molecules or using energy to build them. Inevitably there are left over pieces that are useless and may or may not be recyclable, hence metabolic waste.

4. What are Metabolic Wastes
The cell will want to get rid of this waste as if its allowed to build up it will become toxic to the cell.

5. Quick Question
Brainstorm some metabolic wastes produced in the human body. Where do each of these waste products come from? (Hint: Think about why we sweat and urinate?)

6. Waste Products Waste Product Origin of Waste Product Excretory Organ
Ammonia
Breakdown of amino acids in the liver.
Kidneys
Urea
Conversion of ammonia in the liver.
Kidneys, skin
Carbon Dioxide
Cellular Respiration (breakdown of glucose in the cells)
Lungs, intestines, skin
Water
Cellular respiration (breakdown of glucose in the cells)
Kidneys, lungs, intestines, skin
Mineral Salts
Food and water
Kidneys, lungs