Question

1. Name the phenomenon which helps fresh water unicellular organisms (e.g., Amoeba) continuously gain water in their bodies. Also name the mechanisms by which these organisms throw out excess of water from their bodies. 
2. Give at least two examples in plants where a similar phenomenon is used to gain water.

Answer 1

1. Freshwater Amoeba gains water by osmosis and expels excess water using a contractile vacuole.
2. Examples in plants include water absorption by root hairs and water uptake by plant cells that helps keep leaves and young shoots turgid.