Why are plants green? To reduce the noise in photosynthesis

Re:Why are plants green? To reduce the noise in photosynthesis by delecti on Saturday October 01, 2022 @06:22PM (#33050689)

I'm not sure the same consideration applies to sunblock. The article makes the case that plants always "want" to let through the same quantity of light, but not necessarily the same proportion, while we ideally want to block 100% of UV all the time.

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Re:Why are plants green? To reduce the noise in photosynthesis by dieselerator on Saturday October 01, 2022 @08:06PM (#33051361)

I think this might be a good place to add this reminder:

"Vitamin D is made when UV (more precisely, UVB rays) react with a compound (7-dehydrocholesterol) in the skin. The best rays for UV synthesis have wavelengths between 270–300 nm." [1]

[1] https://www.sciencelearn.org.nz/resources/1313-vitamin-d-and...

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Re:Why are plants green? To reduce the noise in photosynthesis by lightedman on Saturday October 01, 2022 @08:34PM (#33051542)

270nm is UVC territory. Did you mean 280nm instead?

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Re:Why are plants green? To reduce the noise in photosynthesis by dieselerator on Saturday October 01, 2022 @09:33PM (#33051876)

That is a fair question. This is what I find. [1]

Ultraviolet B UV‑B 280–315

Ultraviolet C UV‑C 100–280

[1] https://en.wikipedia.org/wiki/Ultraviolet

My read is "UVB" is the popular medicine way of saying UV is needed for the body to synthesize vitamin D. It was not considered necessary to point out part of the useful spectrum is in "UVC" territory.

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Re:Why are plants green? To reduce the noise in photosynthesis by hinkley on Sunday October 02, 2022 @12:59AM (#33053002)

Also kills microbes on surfaces.

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