1. Water is essential for all forms of life. It constitutes around 65% of the human body and 95% of plants. Water plays an important role in the biosphere owing to its high specific heat, thermal conductivity, surface tension, dipole moment, and dielectric constant. Water is the only source of life to all the living organisms on earth and also to all the marine animals.

2. The high heat of vaporization and heat of capacity of water helps in moderating the climate and body temperature of all living beings. Water is the only source of life to all the living organisms on earth and also to all the marine animals.

3. It acts as a carrier of various nutrients required by plants and animals for various metabolic reactions.