⊕ Parasites are completely dependent on a host for survival. The relationship is beneficial to one, and harmful to the other. Parasites may live outside or inside a host; they are called ectoparasites and endoparasites. An example of the endoparasite is the tapeworms which live in the digestive systems of its host. Examples of ectoparasites are ticks and lice.
⊕This is a beneficial relationship to both partners of different species living together. For example a bee and a pollinating flower. The bee gains nectar from the flower for survival, as it uses the bee to carry its pollen to other flowers. So both organisms living together benefit from their existence.