_AlreadyTaken_

_AlreadyTaken_ t1_j2fp8nf wrote

I even read that purple bacteria appear to be older than chlorophyll photosynthesis. So either absorbing green, the peak of the solar spectrum is TOO much energy (heat can disable the enzymes) or that part of the spectrum was already filled by organisms so the green ones took what was left.

Chlorophyll is also composed of many subunits that likely have been added as enhancing features over time, like energy transmitting antennae structures that funnel the photon energy to the reaction center.

I used to date a woman who was researching the dna structure of photosynthetic bacteria. :D

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_AlreadyTaken_ t1_j2fmtd4 wrote

I'll toss out one more thing to think about. Life clearly evolved on earth before there was any ozone layer and ultraviolet light was bombarding the surface because it appeared before photosynthesis did so there was no free oxygen (or very very little) in the atmosphere to make ozone. So life can develop in spite of UV light, probably in water too deep for UV light to penetrate. Did photosynthesis evolve from mechanisms to protect against UV light in shallow water? Who knows...

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_AlreadyTaken_ t1_j2cdktk wrote

We wouldn't lose our atmosphere, Venus barely has a magnetic field and it has a very thick one. It helps us hold onto lighter elements. Water vapor could be photodissociated into oxygen and hydrogen and the hydrogen stripped away. We could also lose the ozone layer. There is even a weak spot in the magnetic field, the South Atlantic Anomaly.

You don't absolutely need it but it definitely helps.

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_AlreadyTaken_ t1_j29hwlv wrote

>it does make it possible to have atmosphere

You mean a magnetosphere protecting against solar dissociation. This isn't exactly the case, you would still have an atmosphere, you'd just lose the lightest elements like hydrogen. This is bad for earth because it would end up with an atmosphere and surface devoid of water like Venus.

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_AlreadyTaken_ t1_izk9ue0 wrote

Big problem with journalists and medical studies. The paper will have all sorts of conditions on the data but the press will report one finding without these conditions. "Drug X had negative effects on 40% of people with condition Y who take drug Z" becomes "Drug X has negative effects!"

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