Question

The absence of starch in a leaf is shown when iodine solution turns...

Answer 1

The absence of starch in a leaf is shown when iodine solution turns a yellow-brown color. When iodine is present and starch is present, it turns a blue-black color. Therefore, if the iodine solution does not change to blue-black and remains yellow-brown, it indicates that starch is not present in the leaf being tested.