Biological complexity:photosynthesis new research (Introduction)

by David Turell @, Tuesday, March 20, 2018, 17:57 (2222 days ago) @ David Turell

Without photosynthesis our atmosphere would not contain the level of oxygen it has, and more than likely life would not have evolved beyond single cells. We still don't know fully how it works, because the photon action responses are so fast:

https://phys.org/news/2018-03-givin-uncovers-photosynthesis.html

"In photosynthesis, light strikes colored molecules that are embedded within proteins called light-harvesting antenna complexes. These same molecules give trees their beautiful fall colors in Michigan. From there, the energy is shuttled to a photosynthetic reaction center protein that starts to channel energy from light through the photosynthetic process. The end product? Oxygen, in the case of plants, and energy for the organism.

***

"'In photosynthesis, the basic architecture is that you've got lots of light-harvesting antennae complexes whose job is to gather the light energy," Ogilvie said. "They're packed with pigments whose relative positions are strategically placed to guide energy to where it needs to go for the first steps of energy conversion."

"The differently colored pigments wrestle with different energies of light and are adapted to gather the light that is available to the bacteria. Photons excite the pigments, which triggers energy transfer in the photosynthetic reaction centers.

"'The antennae take solar energy and create a molecular excitation, and in the reaction center, the excitation is converted to a charge separation," Ogilvie said. "You can think of that kind of like a battery."

"But it is this moment—the moment of charge separation—that scientists do not yet have clearly pictured. Ogilvie and her team were able to take snapshots to capture this moment, using a state-of-the-art "camera" called two-dimensional electronic spectroscopy.


"In particular, Ogilvie and her team were able to clearly identify a hidden state, or energy level. This is an important state to understand because it's key to the initial charge separation, or the moment energy conversion begins during photosynthesis. They were also able to witness the sequence of steps leading up to charge separation.

"The finding is a particular achievement because of how impossibly quickly this energy conversion takes place—over the span of a few picoseconds. Picoseconds are one trillionth of a second, an unimaginable timescale. A honey bee buzzes its wings 200 times a second. The first energy conversion steps within purple bacteria take place before the bee has even thought about the downward push of its first flap."

Comment: Previous research has shown that quantum mechanics are necessary. try and tell me this is not deigned!


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