Question

In some freshwater organisms there is a structure called a contractile vacuole that regulates water movement into and out of the cell. What explains the existence of the CV?

Answer 1

Freshwater organisms, including single cells such as Paramese or Amoeba, have a type of body called Vacuole, which by pumping out the amount of water enters the cell to extraneous cells from bursting because the cells with this organ lack walls They are cellular because they would have expanded if they had a wall

Answer 2

The contractile vacuole is an structure that helps in regulation of osmotic pressure within the single celled species such as amoeba, paramecium and some algae. The solute concentration in the cytoplasm of these species contains large amount of solute as compared to their surroundings. In order to maintain the solute concentration, excessive water is stored in CV and then expelled out though an opening in the cell