Plants produce oxygen during photosynthesis and utilise oxygen during respiration. They produce much more oxygen during photosynthesis than they consume during respiration.

Earthworms can breathe inside the soil. They come outside only when the water takes the place of air in the soil.

Oxygen present in the air supports burning.

Bats and insects can fly due to the presence of air.

Air is a colourless and odourless mixture of gases.

Mountaineers carry oxygen cylinders with them because at high altitudes, oxygen becomes sparse which causes many complications in the human body. That’s why they need oxygen cylinders to breathe.

The water vapour present in the air condenses and drops of water appear on the cold surface.

They use the oxygen from the air trapped in the pockets of the soil.

The aquatic animals survive under water by taking in oxygen dissolved in water. 

Air consists of gases like nitrogen, oxygen, carbon dioxide, inert gases, water vapours, suspended dust and particulates which envelop the surface of the earth in a layer about 16 km thick. This layer of air enveloping the earth is known as the atmosphere.

Air, water, food and a suitable place to live are necessary for survival.

Due to presence of dust and smoke particles, the windscreen becomes hazy and presence of fog also affects the windscreen.

Air helps in the dispersal of seeds and pollen of flowers of several plants. Air is not the source of nitrogren for plants which they take from soil alone.

The mask will prevent dust and smoke particles from getting into the respiratory system of the policeman.

The  process of combustion cannot take  place in the absence of oxygen. Hence fire can be extinguished by cutting off the supply of oxygen which is the supporter of combustion. 

Air contains water vapours and when air comes in contact with a cool surface, water vapour condenses and drops of water appear on the cooled surface of an object.

The force exerted by the moving air helps the firki to rotate.

The lump of cotton wool shrinks. Air is present in the cotton wool. When it is dipped in water, air present in the cotton wool escapes and it shrinks.

The plants and animals depend on each other for exchange of oxygen and carbon dioxide from air. Plants use up large amounts of carbon dioxide and give out oxygen during photosynthesis and hence they help to maintain the level of gases in the air. 

Animals use air for respiration, plants use air for preparing their food and air helps in power generation by wind turbines.