Class 12th Biology 2016 Set1 Delhi Board Paper Solution
Question 17
Predation is usually referred to as a detrimental association. State any three positive roles that a predator plays in an ecosystem.
Answer
Predation is an interspecific interaction, where an animal,called predator, kills and consumes the other weaker animal called prey. ie. a tiger (predator) eating a deer (prey), a sparrow (predator) eating fruits or seeds (prey) etc.
Role of predators:
Predators keep prey population uner control. This is called biological control. Predators also helps in maintaining species diversity in a community by reducing the intensity of competition among prey species. Besides acting as 'conduits' for energy transfer across trophic level, predagtors play other important roles. In absence of predators species, prey species could achieve very high population densities an cause ecosystem instability.
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