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Light-Dependent Reactions

What would the results be of testing light and dark leaves with IKI. What would the results indicate? Ideas are expressed.

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Starches are long-chain carbohydrates composed of monomers of glucose. Starch is readily detected using a solution of Iodine and potassium iodide (I2KI). When starch is present, a blue colour will form when exposed to this solution. I assume this is what you are referring to.

When photosynthates are produced more rapidly than they can be transported out of the leaf cell, the cell tends to form starch as a storage molecule for the glucose made. This can be used as a method to determine photosynthetic activity. Testing leaves with I2KI thus gives an indication of whether or nor photosynthesis has occurred in those tissues.

In the experiment you have performed, I assume you ...

Solution Summary

The Light-Dependent Reactions are examined.