Question

Some archaea (single cell organisms) live in extremely salty water such as the Great Salt Lake or the Dead Sea. Most types of cells would shrivel and die in this very salty water. How do you think these Archaea prevent water loss while living in very salty water?

Answer 1

Archaea that live in extremely salty water are called as halophiles. Normal organisms would shrivel in high salt condition because water would be pulled out of them. Halophiles have developed several mechanism to avoid this problem.

• The first route is by increasing their osmolarity. They accumulate organic compounds called as osmoprotectants in the cytoplasm from the environment or by synthesis. As a result osmolarity increases inside the cell and water does not move out of the cell.
• Another way is to make potassium ions selectively move inside the cell. The osmolarity is again increased by the influx of ions and hence the organism does not desiccate.

Answer 2

Halophiles are extremophiles that thrive in environments with very high concentrations of salt. Halophiles prevent this loss of water by increasing the internal osmolarity of the cell by accumulating osmoprotectants or by the selective uptake of potassium ions. Hope this helps.