The Role of Contractile Vacuole in Freshwater Organisms
Understanding the Contractile Vacuole
Freshwater organisms have a unique structure called a contractile vacuole (CV) that plays a crucial role in regulating water movement into and out of the cell. This structure is essential for the survival of these organisms in their aquatic environment.
Why Does the CV Exist?
The main purpose of the contractile vacuole is to help the organism maintain osmotic pressure within its cells. Osmotic pressure refers to the pressure exerted by the movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration.
In freshwater environments, the concentration of solutes inside the cell is higher than in the surrounding water. This difference in concentration causes water to move into the cell through the process of osmosis. The contractile vacuole functions by periodically contracting and expelling excess water from the cell, preventing it from bursting due to the influx of water.
The Significance of CV in Freshwater Adaptation
The presence of a contractile vacuole is crucial for the survival of freshwater organisms, as it helps them prevent excessive water intake that could disrupt their internal balance. By regulating water movement, the CV ensures that the organism maintains the right osmotic pressure needed for cellular functions.
Therefore, the existence of the contractile vacuole in freshwater organisms can be attributed to its role in maintaining osmotic balance and preventing the cells from swelling and bursting due to excess water intake through osmosis. It is a vital adaptation that enables these organisms to thrive in their watery habitats.
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? A) The CV prevents the organism from drying out. B) The CV assists the organism in capturing prey. C) The CV helps the organism move through the water. D) The CV helps the organism maintain osmotic pressure.
The correct answer would be option D. The contractile vacuole is a cell organelle mainly involved in the regulation of osmotic pressure. It helps in pumping excess water out of the body. In freshwater organisms, the inside of the cell is hypotonic compared to water outside the body. Consequently, water keeps moving into the cell due to osmosis. The contractile vacuole helps in removing this excess water out of the cell and thus helps regulate the osmotic pressure.