Yes, plants can use the energy of sunlight to make sugar and oxygen. The oxygen is a gas and it gets released into the air.The process is called photosynthesis. What happens is that the plant takes in water and carbon dioxide and converts it with the help of sunlight into sugar and oxygen. To do this it needs the green plant pigment called chlorophyll which gives the leaves of a plant its green color. A pigment is any substance that absorbs light and it is very complex. It makes energy molecule out of sun energy that the plant can then use to form the carbon bonds to make sugar.

As I mentioned before, the plant needs water and carbon dioxide to make sugar. Water and carbon dioxide enter the plant through the cells of the leaf. Water enters through the roots and is transported up to the leaves. Carbon dioxide cannot pass through the waxy layer covering the leaf but it can enter the leaf through an opening called stoma (the stoma = Greek for hole). Likewise, oxygen produced during photosynthesis can only pass out of the leaf through the opened stomata.

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