List of top Science Questions on Environment asked in CBSE Class X

Write the percentage of the energy of sunlight captured by green plants, to convert it into food energy. Explain the fate of this energy when green plants are eaten by primary consumers.
Assertion (A): Carbon and its compounds are our major sources of fuels.
Reason (R): Most of the carbon compounds on burning release a large amount of heat and light.
In the following groups of wastes, which group contains only non-biodegradable wastes?
What does a food chain represent? “The number of trophic levels in a food chain is limited.” Give an example stating reason to justify this statement.
Use of pesticides to protect our crops affect organisms at various trophic levels especially human beings. Name the phenomenon involved and explain how does it happen.
Name the term used for the materials which cannot be broken down by biological processes. Give two ways by which they harm various components of an ecosystem.
Define trophic levels. At which trophic level do we find (i) secondary and (ii) tertiary consumers in a food chain? What will happen if all the organisms of a trophic level die? Give reasons to justify your answer.
List any two methods by which the solid wastes generated in urban areas can be safely disposed off.
State any one advantage of using cloth bags over plastic bags.