In an ecosystem, organisms are dependent on each other for their survival. Small fish eat plankton. In the fish, chemical energy
from plankton is converted into and used by fishes to swim. These fish are then devoured by large fish. Bacteria break down the dead bodies of fish to release energy, which is then absorbed by other organisms in the ecosystem. This flow of energy is an example of the .
This flow of energy is an example of food web or food chain of the marine ecosystem.
The energy flow in an ecosystem in the form of food from one organism to other is food chain. It comprises mainly of three types of organisms producers or autotrophs, consumers or heterotrophs and decomposers. The energy flow in food chain or food web is unidirectional from plants which are the primary producers to primary consumers or herbivores, then to secondary consumers or carnivores and finally to the decomposers. On its unidirectional flow the energy is lost in different form such as heat loss, decay, respiration etc. The energy passed from one level to another is not the same and gets lost in the process so when the energy is received from one tropic level to another it is always less than that received by the previous tropic level.
