Question

Question 9.28 Describe the usefulness of water in biosphere and biological systems.

Class XI Hydrogen Page 290

Answer 1

          as you know, a major part of all living things is made up of water.about 65% of the human body full of water and some plants have as much as 95% water.it is the most important compound for the survival of all life forms.
      water has a high specific heat, thermal conductivity is high, surface tension, dipole moment, dielectric constant etc are also high in water. that's why water plays a vital role in the biosphere. the high heat of vaporization of water is responsible for moderation of the climate and body temperature of living things.it is an excellent solvent for transportation of minerals and nutrients for plants and animal metabolism.
      and most important that water is required for photosynthesis in plants.
  which released O₂ into the atmosphere.
6CO₂(g) + 6H₂O(l) ------->C₆H₁₂O₆ + 6O₂(g)
                                         glucose
 

Answer 2

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.

The high heat of vapourization and heat of capacity of water helps in moderating the climate and body temperature of all living beings.

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