Our Environment Class 10 Science Chapter 13 Important Question Answer NCERT Solution

NCERT Class 10 Science Chapter 13 Our Environment Important Question Answer Solution For School Students of Class 10th. We also Provides Notes and Important Questions for Class 10 Science. NCERT Class 10th Science book is applied in mostly boards like CBSE, HBSE, RBSE, Up Board, MP Board and also some other state boards.

NCERT Class 10 Science Chapter 13 Our Environment Important Question Answer for CBSE, HBSE, RBSE, UK Board, HP Board, MP Board and Other Boards Solution.

Our Environment Class 10 Science Chapter 13 Important Question Answer


Q1. Define ecosystem.

Ans. All the interacting organisms in an area together with the non-living constituents of the environment form an ecosystem. Thus, an ecosystem consists of biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil and minerals.

Example : Forests, ponds, lakes, gardens, rivers etc.


Q2. What are biodegradable substances?

Ans. Those substances which can be decomposed by micro-organisms are called biodegradable substances. eg – fruits, paper, cotton, vegetables etc.


Q3. What are the various biotic and abiotic components of Ecosystem?

Ans. Biotic components : all living organisms

Abiotic components : physical factors like temperature, rainfall, wind, soil and minerals.


Q4. “Flow of energy is unidirectional in ecosystem”, explain.

Ans. Flow of energy is unidirectional in ecosystem means the energy that is captured by the autotrophs does not revert back to the solar input and the energy which passes to the herbivores does not come back to autotrophs. As it moves progressively through the various trophic levels it is no longer available to the previous level.


Q5. In how many directions the energy flows in any ecosystem ?

Ans. The flow of energy in any ecosystem is unidirectional (one direction) .


Q6. What percentage of solar energy captured by green plants is converted into food energy in a terrestrial ecosystem?

Ans. About 1%


Q7. Write full form of UNEP. Most Important

Ans. United Nations Environment Programme.


Q8. The autotrophs capture the energy present in sunlight and convert it into ________ energy.

Ans. chemical


Q9. The higher energy UV radiations split apart some molecular oxygen into _________ atom.

Ans. free oxygen


Q10. Which layer shields the surface of earth from ultraviolet radiations form Sun?

Ans. Ozone layer


Q11. Name the solar radiation from which the surface of earth is shielded by ozone layer.

Ans. ultraviolet (UV) radiation


Q12. Which synthetic chemical is responsible for depletion of ozone layer?

Ans. chlorofluorocarbons (CFCs)


Q13. What are the advantages and disadvantages of ozone ?

Ans. Advantages of ozone : At higher levels of atmosphere, it protect the surface of earth from ultraviolet radiations. These radiations are highly damaging as they cause skin cancer in human skins.

Disadvantages of ozone : On ground level, It is a deadly poison.


Q14. Which organisms act as decomposer ?

Ans. Micro-organisms like bacteria and fungi act as decomposer.


Q15. Write full form of CFCs.

Ans. chlorofluorocarbons


Q16. What is the role of decomposers?

Ans. Decomposers are the microorganisms comprising bacteria and fungi which break down the complex organic substances into simple inorganic substances.


Q17. What are trophic levels?

Ans. Trophic levels are the step or level of the food chain at which transfer of food (or energy) takes place from one organism to another organism.

Green plants → Deer → Tiger

In this food chain, green plants are at first trophic level, Deer is at second trophic level and tiger is at the third trophic level.