Question

Which protozoan is unlikely to have a contractile vacuole [BHU 2001; CBSE PMT 2001]
A) Euglena
B) Paramecium
C) Amoeba
D) Plasmodium

Answer 1

Amoeba
➡️ is unlikely to have a contractile vacuole

Answer 2

An organism that is unlikely to have a contractile vacuole is the D) Plasmodium.

The ‘contractile vacuole’ is a vacuole which is present to regulate the ‘water content’ of the cell. This is done through a process called osmoregulation.

They are mostly present in freshwater organisms in which the salt content is excess inside the cell than the outside. Among the above Plasmodium is a parasite that is terrestrial and does not require osmoregulation.