Explanation: A food chain may be defined as the transfer of energy and nutrients from the source in plants through a series of organisms with repeated processes of eating and being eaten. Parasitic rood chain starts from herbivore but food energy passes from larger to smaller organism without outright killing as in case of predator. Hence, the larger animals are considered to be the hosts and the smaller animals which fulfill their nutritional requirements from the hosts are considered as parasites. ....Read more