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I can't find anything about this on the net.

I read in my (high-school) textbook that if plants get sunlight, water and carbon dioxide, and the catalyst called chlorophyll, they can make sugar.

I'm just thinking... We CAN extract chlorophyll by dissolving the boiled leaf in ethanol! So can't we just bubble CO2 in and let the sun shine on it and add some water? Shouldn't that make sugar in the solution?

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    $\begingroup$ An interesting thought, but your textbook has presented photosynthesis in a highly simplified way. I suggest you go through khanacademy.org/science/biology/photosynthesis-in-plants (it's fairly detailed!). Then think again about why the method you described may or may not work. $\endgroup$ – Adhish Sep 9 '20 at 12:56
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The mechanism of photosynthesis proceeds via light-dependent reactions and light-independent reactions within the chloroplasts (organelles in cells which house the photosynthetic machinery, and indeed chlorophyll itself).

To produce glucose via photosynthesis, you certainly need the pigment chlorophyll - it is necessary but not sufficient by itself. For that, you need the Calvin cycle, which is part of the light-independent reaction within photosynthesis.

The light-dependent reaction requires chlorophyll and uses H2O and sunlight to produce ATP and NADPH, with oxygen as a byproduct. ATP and NADPH are necessary for the Calvin cycle to proceed, which takes atmospheric CO2 and produces glucose and other sugars. This is simplified into basic photosynthetic equation which you are familiar with.

     6 CO2     + 6 H2O  -->  C6H12O6 +  6 O2
carbon dioxide + water  -->  glucose + oxygen

Here is an illustration:

enter image description here

The red arrows point to the light-dependent ("light"), and light-independent ("dark") reactions.

Take a look at this slideshow, which answers all your questions with illustrations.

We CAN extract chlorophyll by dissolving the boiled leaf in ethanol! So can't we just bubble CO2 in and let the sun shine on it and add some water? Shouldn't that make sugar in the solution?

Unfortunately you destroy the chloroplast structures during the extraction you describe. These structures, and especially the membranes, are necessary for photosynthesis in its entirety to proceed.

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