Question

why the upper surface of leaf is much darker?​

Answer 1

The upper surface of leaf is much darker than the lower surface because the upper surface is more exposed to sunlight and for better trapping of the heat, more chlorophyll is present on the upper surface of the leaf and makes it look much darker.

Answer 2

✯Answer✯

As the upper surface of the leavesare darker as compared to the lower side, similarly, upper surfaceof dicot leaves are darker than the lower sides. This is because they receive more sunlight than the lower ones. Therefore, they containmore chlorophyll. So, as a result they colour is darker than the lowerside.