Parasitism : It is a relationship between two species in which one benefits at the expense of other. Types of Parasitism :
(a) Ectoparasites : Parasites living on the surface of the host are called ectoparasites. eg. flea, mosquito, lice etc.
(b) Endoparasites : Parasites seen in the interior of the host body are called endoparasites eg. Flatworms, tapeworm etc. Endoparasites are of two types, intercellular and intracellular. Intercellular endoparasites inhabit intercellular spaces whereas intracellular endoparasites live within the cells of the host body.
