Why do leaves turn shades of yellow, orange and red in Autumn?
Chlorophyll is the substance present in leaves which gives them their intense green colour in summer. Chlorophyll is vital in the process of photosynthesis, the means by which plants convert light energy into chemical energy. Sunlight is absorbed into the leaf by chlorophyll. Photosynthesis carbon dioxide + water + light energy + chlorophyll = glucose + oxygen However chlorophyll is not a very stable compound and bright sunlight causes it to break down. To maintain the amount of chlorophyll in their leaves, plants continually have to make it. Summer During the spring and summer chlorophyll is continually broken down and re-made in the leaves of plants and trees in the strong sunlight and warm temperatures which generally accompany these months. The intense green colour of the chlorophyll masks the other plant pigments which are present in the leaves the red, blue and purple anthocyanins, and the yellow and orange carotenoids. Cranberries, red apples, cherries, strawberries are some of
