When testing the color of the leaves for the presence of starch using iodine, you probably will not see some blue/black color change. Explain why?

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The color change to blue or black indicates the presence of starch. These are also areas that possessed chloroplasts, which possessed chlorophyll, a green pigment. The chloroplasts are what are needed in a plant leaf to conduct the process of photosynthesis, which is what produces the starch, in the form...

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The color change to blue or black indicates the presence of starch. These are also areas that possessed chloroplasts, which possessed chlorophyll, a green pigment. The chloroplasts are what are needed in a plant leaf to conduct the process of photosynthesis, which is what produces the starch, in the form of glucose. Areas in the leaf that do not exhibit this black or blue color change are areas that are devoid of starch, meaning there was no chloroplasts present to conduct the production of starch. Sometimes, there are extenuating circumstances, such as the leaf did not receive any sunlight, which is a necessary requirement for photosynthesis to take place. Plants that are in limited sunlight or subject to overcast days have limited starch production due to the fact that there was not enough light energy available to fuel the photosynthetic process. In any event, a failure on the color change indicates an absence of starch, for whatever reason.

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