Question

How can an Amoeba survive in a hypotonic environment?

Answer 1

Hint: Amoeba’s natural habitat is fresh-water such as rivers, lakes, and ponds. They can also be found in hot springs and industrial discharged water. They can also be found in isotonic conditions. The difference between Amoeba living in hypotonic conditions and isotonic conditions is the presence of contractile vacuole which is present in Amoeba living in hypotonic conditions. They prevent them from bursting.

Complete answer:
-All fresh-water Amoeba lives in hypotonic conditions. A cell living in hypotonic conditions dies.
-All hypotonic solutions are the one in which there is lower solute concentration than the cell. A cell living in hypotonic conditions dies as it swells up and bursts.
-In osmosis, the fluid moves from lower concentration to higher concentration through a semipermeable membrane. In the case of Amoeba, the cell membrane acts as a semipermeable membrane. So the fluid moves in the cells. But somehow it doesn’t swell up and burst.
-Because Amoeba has a special type of organelle called the contractile vacuole. These vacuoles constantly expelled water out of the cells. The rate of expelling the water is maintained according to the rate of absorption. This helps in maintaining constant internal metabolism. So this is how the Amoeba survives in the hypotonic solution. This mechanism is also seen in Paramecium.

Note: This mechanism is also seen in Paramecium. The difference between the two is that the Amoeba has only one contractile vacuole while Paramecium can contain up to two to three contractile vacuoles. There are radiating canals present in the cytoplasm which absorb the water and direct them to the contractile vacuole.