Water Relations Of Cell

Water potential is a measure of the tendency of water molecules to move from one area to another, represented by the symbol Ψ. Water flows from an area of higher water potential to one of lower water potential.

OSMOSIS IN CELLS

The presence of solute molecules in a solution reduces its water potential, which is referred to as solute potential. Solute potential is always negative and increases with the concentration of solute molecules.

Applying pressure to pure water or a solution increases its water potential, which is known as pressure potential. In living cells, pressure potential can increase when water enters by osmosis, causing the cell to become turgid.

Water potential can be calculated as the sum of solute potential and pressure potential. Osmoregulation refers to the regulation of water content and solute concentration in body fluids, particularly sodium, potassium, and chloride ions.

Plants have various adaptations to maintain water content and survive in different habitats. Hydrophytes are freshwater plants that take up water by osmosis and become turgid when the water potential of the cell is equal to that of the surrounding water. Halophytes are plants that inhabit areas with high salinity and have adaptations to conserve water and regulate salt content. Mesophytes are the majority of angiosperm species and occupy areas with adequate water supplies, while xerophytes are adapted to life in dry regions and have features to reduce water loss and store water.

A Hydrophytic plant

Euphorbia virosa a Hydrophytic plant