EVERYDAY SCIENCE

Detailed explanation-1: -A parasite is an organism that lives on or in a host organism and gets its food from or at the expense of its host. There are three main classes of parasites that can cause disease in humans: protozoa, helminths, and ectoparasites. Entamoeba histolytica is a protozoan. A microscope is necessary to view this parasite.

Detailed explanation-2: -Viruses are small and relatively simple microbes that cannot grow outside of living cells, that is, they are obligate intracellular parasites (Figure 1).

Detailed explanation-3: -Parasites like tapeworm and roundworm live inside the internal organs or tissues of their hosts and derive nutrition from them. Such parasites are called as endoparasites.

Detailed explanation-4: -Viruses are not made out of cells, they can’t keep themselves in a stable state, they don’t grow, and they can’t make their own energy. Even though they definitely replicate and adapt to their environment, viruses are more like androids than real living organisms.