Parasites have heterotrophic mode of nutrition where a parasitic organism lives on the body surface or inside the body of another type of organism (a host) and gets nutrition directly from the body of the host. For Example: Plasmodium, Lice, tape worm, round worm etc. And decomposers are organisms that get energy by decaying or breaking down chemically the remains of dead organisms. When an organism dies, decomposers decay the body extracting the last bit of energy from it. For example: fungi and bacteria.
