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Organisms and Populations — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations5 Marks
Question
Discuss the various types of positive interactions between species.
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Answer

Following are the positive interactions between species:
  1. Mutualism: This is a relationship between two organisms in which both the organisms are benefitted. Lichen is a very good example of mutualism. Lichen is an association of fungi and algae. The fungal part attaches to the substratum and gets water and minerals for the algal part. The algal part carries out photosynthesis and provides food to the fungal part.
  2. Commensalism: This is a relationship between two organisms in which one organism is benefitted, while another organism is neither at gain nor at loss. Egrets keep on sitting on the back of herbivore animals; like buffalo, cow, etc. when the cattle forage for grass, the insects under the grass fly away haphazardly. This gives a chance to the egrets to feed on insects.

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