Question

Describe briefly about the balancing mechanism of aquatic vertebrate

Answer 1

Osmosis is the diffusion of water across a membrane in response to osmotic pressure caused by an imbalance of molecules on either side of the membrane. 
Osmoregulation is the process of maintenance of salt and water balance ( osmotic balance) across membranes within the body’s fluids, which are composed of water, plus electrolytes and non-electrolytes.
An electrolyte is a solute that dissociates into ions when dissolved in water.
A non-electrolyte, in contrast, doesn’t dissociate into ions during water dissolution. Both electrolytes and non-electrolytes contribute to the osmotic balance.
The body’s fluids include blood plasma, the cytosol within cells, and interstitial fluid, the fluid that exists in the spaces between cells and tissues of the body.
The membranes of the body (such as the pleural, serous, and cell membranes) are semi-permeable membranes.
Semi-permeable membranes are permeable (or permissive) to certain types of solutes and water.
Solutions on two sides of a semi-permeable membrane tend to equalize in solute concentration by movement of solutes and/or water across the membrane. 

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