Host Defenses
Hosts respond to parasitisms in many ways ranging from the morphological to the behavioural. In some cases, plants produce toxins to deter parasitic fungi and bacteria. Vertebrate animals have developed complex immune systems, which can target parasites through contact with bodily fluids. Animals are also known to resort to behavioral defenses, examples of which are the avoidance by sheep of open pastures during spring, when roundworm eggs accumulated over the previous year hatch en masse; and the ingestion of alcohol by infected fruit flies as self medication against blood-borne parasites. In humans, parasite immunity is developed prominently by Immunoglobulin E antibodies.
Read more about this topic: Parasitism
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