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Organisms and Populations

Short Answer Type

31. What is brood parasitism ? Give an example.

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32. List a few adaptations which parasites have developed.

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Long Answer Type

33. Define mutualism. Give examples.

Mutualism. It is a symbiotic relationship between the members of two species in which the two partners are mutually benefited. There is a complete dependence of the partners on each other, and one cannot survive in the absence of the other. Sometimes the term symbiosis is used as synonym with mutualism.

Examples. 1. Mutualism between Rhizobium and leguminous plants. The rhizobium bacteria helps the plant to fix nitrogen whereas the plant provides food and shelter to the bacteria.

2.Mutualism between plants and fungus. Lichens involve the symbiotic association of a green alga and a fungus. The fungus provides protection to algae whereas the algae provides food to the fungus

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