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Name: Ryan
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Is there any reason for plant guard cells to have chlorophyll even though light is hard to reach the lower part of the plant?


Found this article that might be helpful:


Anthony R. Brach, PhD
Missouri Botanical Garden
c/o Harvard University Herbaria

Dear Ryan,

I might rephrase your question and ask, is there a reason to have chloroplasts in guard cells? Guard cells have a specialized function in the leaf, as you know, and the presence of chloroplasts and their unique biochemistry in guard cells may support that function better than a cell lacking chloroplasts. Alternatively, even though light intensity is attenuated by the leaf mesophyll cells and guard cells are typically found on the undersides of the leaf, there can be sufficient light intensity to drive photosynthesis above the compensation point.

Jim Tokuhisa, Ph.D.
Assistant Professor

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