Water plays an important role in a large number of processes like digestion, transport and excretion which take place in the human body. It also helps regulate the body temperature of human beings. This is discussed below-
Water is a good solvent so the nutrients and salts present in our food get dissolved in water. These dissolved nutrients and salts are then easily absorbed by our body.
All the metabolic reactions of the body take place in the aqueous medium (or water medium). In other words, water acts as a medium for all the metabolic reactions which take place in the body.
Water dissolves the waste materials of the body (like stool, urine, etc.) and hence provides a good medium for excreting the body wastes.
Water regulates the temperature of our body by the process of sweating and evaporation. This can be explained as follows- when the outside temperature is high, then water oozes out through the skin pores of the body in the form of sweat. When this water (or sweat) evaporates from our body, it takes the latent heat of vaporization from the skin. By losing heat, the skin cools down a little bit and we feel comfortable.
Role of Water in Plants:
The role of water in the life of plants is as important as in the human body. Water plays an important role in the life of plants right from the germinating stage. This is discussed below-
Water helps in the germination of seeds and the growth of plants.