Why do leaves fall in autumn?
The green colour in the leaves is due to a pigment, chlorophyll, in the plant. In autumn, the leaves stop making this pigment, thus the leaves turn yellow. Every leaf has a large vein underneath which carries water for nourishing it. This soon becomes dry in a yellow leaf so that water no longer flows through it. Thus the leaf dies and its grip on the branches loosens. When a strong wind blows, it breaks the leaf's grip and thus the leaves fall off in autumn.
No comments:
Post a Comment