Question

"The process used to remove excess water from the paramecium by the contractile vacuole is

(1)synthesis
(2)digestion
(3)active transport
(4)passive transport
"

Answer 1

The contractile vacuoles serves the purpose of osmoregulation in the protozoa and the unicellular algae. The contractile vacuoles pumps the water out from the cell, thus, avoiding the cytolysis (the bursting of the cell membrane) which might occur of the water keeps on accumulating inside the cell. The contractile vacuole eliminates this water from the cell using the active transport process.

Hence, the correct answer is option (3) - active transport.

Answer 2

I think the correct answer from the choices listed above is option 3. The process used to remove excess water from the paramecium by the contractile vacuole is active transport. The contractile vacuoles paramecia used to eliminate excess water are physical pumps.