Question

Some protists, like the Paramecium pictured, live in freshwater. Paramecium have contractile vacuoles, which act to pump water out of the cell. Why?
a. There is a lower solute concentration inside so water is moving into the cell constantly
b. There is a higher solute concentration inside so water is moving into the cell constantly
c. There is a lower solute concentration inside so water is moving out of the cell constantly
d. There is a higher solute concentration inside so water is moving out of the cell constantly

Answer 1

The contractile vacuole acts to regulate quantity of water in a cell. In freshwater environments the concentration of solutes inside the cell is higher than outside the cell

Answer 2

that is what I know