Question

Contractile vacuole in protozoan Amoeba is meant for

• A. respiration
• B. excretion
• C. locomotion
• D. osmoregulation

Answer 1

Answer: (D)

osmoregulation

Answer 2

Contractile vacuole is the clear rounded, pulsating body present in the posterior part of endoplasm of Amoeba. It is found only in fresh water forms and is mainly concerned with osmoregulation, ie, removal of excess of water.
Plasmalemma, a trilaminar and selectively permeable membrane covering the body, functions both in excretion (ammonia) and respiration in Amoeba.
Pseudopodia (false feet) are finger-like and blunt-extensions of cell body in protozoans. In Amoeba, the type of pseudopodium found in lobopodium, composed of both ectoplasm and endoplasm. It is temporary locomotory structure which is also meant for feeding in Amoeba. Locomotion of Amoeba is known as amoeboid movement (Sol-gel theory).