What have we learnt? Plants need the sun’s light to make food. If they do not get enough sunlight the leaves become yellow and fall off. The plant will die. Plants and animals also need air for survival. Air is made up of several gases. All living things need oxygen. This is one of the gases found in air. Plants use up carbon dioxide (another gas found in air), water and sunlight to make food. Plants release oxygen into the air. Animals breathe in air and use the oxygen from the air to stay alive. There is a special gas in the air that all living organisms need to keep them alive. This gas is called oxygen. Plants are living things so they, too, need air to keep them alive. How can we tell? Something to do 1. Take two potted plants and label them A and B.
A
B
2. Put both plants outside in the open yard. 3. Cover plant B tightly with a plastic bag so that air cannot get in. 4. Water both plants everyday. Leave them for about seven days then record your observations.
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