Question

A mutually beneficial association necessary for survival of both partners is

(a) mutualism/symbiosis

(b) commensalism

(c) amensalism

(d) both A and B.

Answer 1

A mutually beneficial association necessary for survival of both partners is mutualism/symbiosis.

Both the partners benefit from the association. The association can be either obligate where the survival of one or both organisms is dependent on another or it could be facultative where both the organisms benefit but it does not define their survival.

Example of obligate mutualism - lichens ( symbiotic association between fungi and algae where the fungus receives nutrition or food prepared by algae and algae receive stability and protection) , nitrogen fixing bacteria (nostoc, anabaena) and leguminous plants.

Examples of facultative mutualism - Ants and aphids - ants receive the honeydew produced by aphids while aphids receive protection from insects , plant pollinators and flowers, clownfish and sea anemones.