Parasitic adaptations

Parasite show many different adaptations of overcoming these challenges, depending on whether they are ecto-parasites or endo-parasites.

1. Many endoparasites show degeneration, or even total loss of certain organs which reduces their energy and material requirements and hence a reduced burden on their host. For example, gut parasites like the tapeworms lack an alimentary canal.
2. Many parasites especially ecto-parasites have attachment devices such as sucker, hooks or anchors enabling them to cling to the host. Tapeworm has hooks and suckers to anchor on host digestive canal.
3. Some parasites have penetrative devices for gaining entrance into the host and its cells. For example, miracidum larva of the liver fluke, has a slender tip on to which open a group of glands which secrete tissue- digesting enzymes. By softening the tissue, the enzyme enables the larva to bore into the foot of a freshwater snail the intermediate host.
4. Gut parasite live in a particularly hazardous environment. They typically have protective device which protects their being harmed by the host’s digestive processes. These devices include the possession of a thick protective cuticle, the secretion of large quantities of mucus and the production of inhibitory substances which locally inactivate the host’s digestive enzymes.
5. To protect themselves from the host’s immune system, some parasites such as the blood fluke, schistosoma, that cause, bilharzia, synthesizes chemicals, which switch of the host’s immune system; The parasite coat’s itself with molecules which the host recognizes as self.
6. Parasite overcome a problem of moving from one host to another by a number of strategies, one of which is to wait until the host mates. The various organism responsible for sexually transmitted diseases in human spread in the same manner
7. Many parasites employ a secondary or intermediate host which conveys the parasite from one primary host to another. Thus, the Anopheles mosquito transfers the malaria parasites from one person to another.
8. To raise the probability of success vast number of offspring are produced
9. The parasites may have a dormant resistant stage in its life cycle to survive adverse conditions until a suitable host is found.
10. Some parasites are closely linked with their host that their tissue are actually interconnected.

E.g., certain plant parasites such as mistletoes plug into other plants and tap off nutrients from the host’s tissue.

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Dr. Bbosa Science