PHOTOSYNTHESIS

Photosynthesis is the process by which green plants produce food. The action of light on carbon dioxide and water syntheses carbohydrates. The process is complex but it can be simplified in the following equation.

Chlorophyll is the substance which makes plants green. It is essential to the process. Glucose is a carbohydrate which plants need. The equation shows how the water molecule is split, and yields oxygen as a by-product. Sunlight provides the energy for the whole process, which takes place in the chlorophyll layer of leaves. Leaves have to be broad enough to catch and absorb the amount of sunlight needed by the plant. The carbon for the process is obtained from atmospheric carbon dioxide. This is absorbed through stomata which are small openings on the underside of leaves.

The hydrogen for the process comes from water which is drawn up from the soil through the plant’s roots. Plants give off the excess oxygen which is vital to the growth of living cells in other forms of life. Sugars, such as glucose, are used by plants as a source of energy. They are the foods which plants need in order to grow. Plants, in turn, provide food for all other forms of life.

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