Question

What type of adaptations do prokaryotes have that allow them to survive in Estuaries?

Answer 1

Prokaryotes are well recognized as essential members of the biosphere. They inhabit all possible locations in which life exists from those offering ideal conditions for growth and reproduction to those representing extreme environments at the borderline of abiotic conditions. An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water and to riverine influences such as flows of freshwater and sediment.

The mechanisms used by prokaryotes to  withstand and physiology to changes in the salt concentrations in their environments are:

Biological membranes are permeable to water. Therefore, water moves into and out of cells driven by differences in water activity between the cytoplasm and the outside medium. Active inward pumping of water lost to the medium when cells are suspended in a high-salt medium with intracellular environment isosmotic with the outside medium. Maintenance of outward-directed pressure is essential as the driving force for cell expansion. This means that the osmotic pressure of the cytoplasm must even exceed that of the outside medium.