Life on the Earth

  • Question 37

    What is a biome ?

    A large area with distinct groups of plants and animals.
    Question 38

    What is ecological balance?


    Ecological balance is a state of dynamic equilibrium within a community of organisms in a habitat or ecosystem.

    Question 39

    Explain the term ‘Ecological Pyramid’.

    1. Each group of organisms occupies a feeding level called a trophic level. The different trophic levels may be represented in the form of a pyramid called ecological pyramid.

    2. Man is at the top of the ecological pyramid. The pyramid has a large base.
    3. It represents primary producers. From base to the top, the numbers go on deceasing at each trophic level.
    4. All green plants and other producers occupy the first trophic level. Herbivores which feed on plants occupy the second trophic level. Carnivores that eat herbivores are at the third trophic level.
    5. At each level, the flow of energy is reduced; because only a fraction of energy is transferred from lower to higher level.

    Question 40

    What do you understand by the term ‘ecology’ ?

    Ecology is the study of the earth as a household of plants, animals and microorganisms. They all live together as interdependent components. In the words of Earnest Hackles “The study of interaction between lifeforms (biotic) and physical environment (abiotic) is the science of ecology”.

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