Excretion in protozoa
- Metabolic waste products in protozoa pass out either by diffusion through the body surface membrane or by means of contractile vacuole, which plays osmoregulatory function.
- In case of B. coli, spiral opening called cytopyge is present through which waste materials are excreted.
Respiration
- Most protozoa absorb oxygen through body surface and remove CO2 through respiratory vacuole.
