Why does fruit change colour as it ripens?
Colourful chemicals in ripening fruit help to preserve it and signal to animals that they are ready to eat.
Asked by: Gargi Phadke, India
Unripe fruits are green because of chlorophyll in their cells. As they ripen, the chlorophyll breaks down and is replaced by orange carotenoids and red anthocyanins. These compounds are antioxidants that prevent the fruit from spoiling too quickly in the air. Fruit-eating animals have also evolved to use the colour change as a sign of ripeness and this helps the plant too, since they need animals to eat the fruit to distribute their seeds.