Red Acer Photosynthesis

[KeenTeen17]

I was just wondering how trees with red leaves are able to photosynthesise because I thought chlorophyll was green

[tameblackbirds]

good question not sure either but sure someone will

[svenrufus]

It's been a long time since I studied this, so I might be a bit shaky on the detail - and it might not apply exactly as stated for red acer, but in general terms, I'm pretty sure that the answer is something like this.

First of all, there are different photosynthetic pigments that are active and most efficient at different wavelengths of light, so lack of green/chlorophyll does not mean no photosynthesis takes place. The reason green is the most abundant colour in the photosynthetically active orders is that this is the wavelength of light that all/most pigments are least effective at harnessing, so that is what we see. The obvious examples are brown seaweeds etc. In fact, there is more than one pigment involved in 'basic' photosynthesis, it is just that the green is most obvious one.

Other pigments include anthocyanin, which is red, carotene, which is yellow, and a number of others which I forget just now.

So, while I'm not exactly sure about red acer, I'm confident that the answer is either - "Other (red) pigments are doing the photosynthesis that you would have expected (green) chlorophyll to do" or at least it will be "There is still chlorophyll there, but there are red pigments there too which mask the colour but are still photosynthetically active"

Hope that helps
Sven

[aeshna5]

Yes I think there is chlorophyll in the red Acer but is masked by the red pigments.

[KeenTeen17]

Originally Posted by svenrufus

It's been a long time since I studied this, so I might be a bit shaky on the detail - and it might not apply exactly as stated for red acer, but in general terms, I'm pretty sure that the answer is something like this.

First of all, there are different photosynthetic pigments that are active and most efficient at different wavelengths of light, so lack of green/chlorophyll does not mean no photosynthesis takes place. The reason green is the most abundant colour in the photosynthetically active orders is that this is the wavelength of light that all/most pigments are least effective at harnessing, so that is what we see. The obvious examples are brown seaweeds etc. In fact, there is more than one pigment involved in 'basic' photosynthesis, it is just that the green is most obvious one.

Other pigments include anthocyanin, which is red, carotene, which is yellow, and a number of others which I forget just now.

So, while I'm not exactly sure about red acer, I'm confident that the answer is either - "Other (red) pigments are doing the photosynthesis that you would have expected (green) chlorophyll to do" or at least it will be "There is still chlorophyll there, but there are red pigments there too which mask the colour but are still photosynthetically active"

Hope that helps
Sven

thanks for all that. you did well. it all makes sense to me now.

[Poirot]

things like this make you appreciate how diverse and adaptive nature can be

[RobSutton]

Originally Posted by aeshna5

Yes I think there is chlorophyll in the red Acer but is masked by the red pigments.

Spot on - sometimes (especially in seaweeds) the other pigments act as secondary receptors which absorb wavelengths of light that chlorophyll can't absorb and transfer the energy along to the chlorophyll to turn into sugars (there are two types of chlorophyll a and b - oversimplifying things one receives energy the other uses it).