Question

Many freshwater animals cannot survive in the Marine Environment. Explain.

Answer 1

Hint: The seawater is salty and hypotonic to the cells of the body which led to exosmosis. A wide variety of species from insects to amphibians, reptiles, fishes, birds, and even mammals live in freshwater. The organisms that live in the freshwater vary from one area to another.

Complete answer:
-In the Marine environment many freshwater fishes are not able to survive because their bodies are not adapted to the marine water.
-There is a high concentration of salt in marine water and in such hypotonic conditions freshwater animals suffer osmotic problems. The bodies of the freshwater animal start to lose water by exosmosis.
-Therefore the freshwater animals it is difficult to survive in the Marine environment.

Additional Information: -The Marine animals also not able to survive in the freshwater because their bodies adapted to the high concentration of salt solutions. The water continues to enter their bodies until all their cells accumulate the water. As a result, they bloat and die eventually.
-In the same way, freshwater animals are also not able to survive in the ocean or salty water because seawater is too salty for them. The water which enters their body continues to flow out of their cells and they will die because of dehydration.
Both processes are called Osmosis.
-Movement of liquid molecules through a semipermeable membrane is known as osmosis. Moment of a liquid takes place from a low concentrated solute to a high concentrated solute.
-A semipermeable membrane has a-holes that are big enough to let liquid molecules enter but they are small enough to block the flow of salt, sugar, or other concentrated contents. So, they usually block large molecules and allow the smaller molecules to pass through them(water molecules)
That’s why freshwater animals die because of dehydration.

Note: -Tonicity is the capacity of a solution to exert osmotic pressure on a membrane and freshwater animals have a lot to do with this principle.
-Generally, there are three types of Tonicity. They are - Hypertonic, Hypotonic, and Isotonic.