Question 2:

__________ and agricultural activities are responsible for emission of greenhouse gases into the air. Trees clean the air by storing carbon dioxide, but due to heavy deforestation air pollution is on the rise.

Question 3:

The layer of air above the earth’s surface is called __________. 

Question 4:

_____ occur when air gets polluted with sulphur dioxide and nitrogen oxide. Then they mix with water particles in the air to form a toxic substance. ________ lead to increased growth of algae, which leads to eutrophication.

Question 5:

Soil is classified on the basis of its nature and composition. In India we find six main types of soils: 1. _______ , which is rich in loam and clay; 2. _______ , which has predominantly clay; 3. ______, which is sandy to loam; 4. ______, which is stony sandy soil; 5. ______, which is sandy and poor in organic carbon; and 6. ________, which has porous clay rich in iron and aluminium hydroxides.

Question 6:

_______ are valuable natural resources and they are crucial for our industrial, technological and cultural growth. They are classified into fuel, metallic and non-metallic. 

Question 7:

________ minerals include sand, gravel, cement, salt, sulphur, phosphorous, diamonds and gems.

Question 8:

______ leads to blocking of sunlight from entering water bodies and reduces oxygen values in water, which creates an inhabitable environment.

Question 9:

Burning of ________, wood and rubber also release harmful gases and pollutes the air.

Question 10:

Just like bees, ____ also supports pollination, as pollens get blown away by ___ from plants,  cross pollination takes place.