Question

Why do paramecium have contractile vacuoles?

a) To aid in reproduction
b) To assist in digestion
c) To regulate water balance
d) To facilitate locomotion

Answer 1

Paramecia have contractile vacuoles to regulate water balance by collecting and expelling excess water, preventing the cell from bursting in a hypotonic medium.

Step-by-step explanation:

Paramecia have contractile vacuoles to regulate water balance. Water constantly enters these freshwater protists because the solute concentration in the cytosol is always higher than the freshwater they live in. The contractile vacuoles collect excess water and then contract to expel the water, preventing the cell from bursting in a hypotonic medium.