Explain why removal of faeces or undigested food from the body is not an example of excretion? [3 MARKS]
Each point: 1 Mark
1. Faeces are undigested food material and its removal is called as egestion.
2. Excretion, by definition, is the removal of metabolic waste products. Thus, these waste products are created as a result of chemical reactions happening in the body. They are not ingested and leftovers.
3. Removal of metabolic wastes usually takes place by urination and sweating. Exhalation is also excretion of carbon dioxide.