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Organisms and Populations — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations4 Marks
Question
  1. How is amensalism different from parasitism and competition? Give an example for each.
  2. Define predation.
✓

Answer

  1.  
 
Amensalism
Parasitism
Competition
1
It is an interspecific interaction in which one is harmed and the other is neither benefitted nor harmed.
It is an interspecific interaction in which one species, called parasite takes shelter and food from another living organism, called host and in due course of time damages the host.
It is a type of interaction either among the individuals of same species (intraspecific), or between individuals of different species (interspecific), for the same resources.
2
Neither of the partners is benefitted.
One of the partners is benefitted.
None of the partners is benefitted.
3
Example: Antibiotics secreted by certain fungi kill some bacteria in the vicinity.
Example: Cuscuta living on the hedge plants.
Example: flamingoes and fishes competing for food (zooplanktons) in a lake.
  1. Predation is the interspecific interaction in which a larger animal (predator) kills and consumes a smaller animal (prey) or an animal (herbivore) eats a plant as food.

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