Question

When a fresh water protozoan is placed in marine water?

• A. The contractile vacuole disappears
• B. The contractile vacuole becomes bigger in size
• C. The number of contractile vacuoles increases
• D. The contractile vacuoles remain unchanged

Answer 1

The correct option is A The contractile vacuole disappears

When a freshwater protozoan is placed in marine water then the protozoan dies. Freshwater protozoans have the ability to produce contractile vacuole which helps in the survival of protozoan from osmosis. It means, the contractile vacuole disappears.