Question

Water is important for the body of animals?
A. Reproduction
B. Keeping the body cooled
C. Working as a solvent
D. All the above

Answer 1

Hint: Water is important for all living organisms. Life originated from water and then throughout the world. All living organisms require water throughout their life and to conduct all the biological functions.

Step by step answer: Reproduction is one of the fundamental characteristics of living organisms. It can be defined as the process that helps in the production of new individuals. Some aquatic organisms require water as a medium for reproduction. Fertilisation is an important step in reproduction; it involves the fusion of egg and sperm. In some animals, fertilisation is external. In external fertilisation, females lay eggs in water, and sperm have to swim through water to reach the egg. In external fertilisation, water provides a medium for the fusion of egg and sperm. Water also helps in maintaining the temperature of the body in animals. The main source of controlling body temperature by water is sweat.
When the external temperature of the body is high, the human body produces sweat and evaporation of sweat results in cooling of the body. Sweat glands generate sweat for cooling down the body temperature. The composition of sweat is mostly water and some amount of potassium, salt and some other minerals. Water has the ability to dissolve more solute in comparison to other solvents. Hence it is known as the universal solvent. Animals require water to dissolve nutrients, minerals and oxygen so transport of these substances becomes easy throughout the body. So, many of the organisms require water for reproduction, keeping the body cooled, and it also acts as a solvent.
So, all the options are correct.

Hence the correct option is (D).

Note: About 60% of the human body is made from water.73% of the brain and heart is composed of water.83% of the lungs is made up of water. The skin consists of 64 % of water and muscle and kidney 79 %. The composition of bone also contains 31% of water.