Give reason to justify the following:

(a) The existence of decomposers is essential in a biosphere.

(b) Flow of energy in a food chain is unidirectional.

(a) The importance of existence of decomposers in biosphere-

(i) The decomposers help in decomposing the dead bodies of plants and animals, hence act as cleansing agents of environment.

(ii) They help in maintaining the fertility of soil by putting back the elements of which the dead plants and animals are made back into soil, air, water for reuse by producers like crop plants.

(iii) In this way, the decomposers also help in maintaining the cyclic process of life and death. They also helps in recycling the material in the ecosystem so that the process of life may go on and on like an unending chain.

(b) The sequence of living organisms in a community in which one organism consumes other to transfer energy of food, is the food chain. It is single direction transfer of energy where the smaller plants or animals are eaten by larger ones, which are further eaten by other animals. For example- grass (producer) is eaten by deer (herbivore) which is eaten by lion (carnivore). Thus, the energy produced by photosynthesis and stored in producers is transferred to herbivores and then to carnivores in a unidirectional flow.