Question

why is it necessary to use two leaves placed at the same time in different conditions (darkness/light) is doc.c alone sufficient?

Answer 1

Two green plants are kept separately in oxygen free containers, one in the dark and the other in continuous light

Step-by-step explanation:

In order to prevent the previously formed starch from interfering, we remove the starch and it is done by keeping the plant in dark. When the plant is in dark, the photosynthesis does not occur and the stored starch is used up.