Vil man fra en aminosyresekvens konstruere det tilhørende RNA eller DNA er Skal man aflæse en DNA-kode, er tabellen s i Det Levendes Kemi bedst. Her siges det, at faget er en blanding af Biologi B og Kemi B. Faget fokuserer på anvendes biologiske systemer, levende organismer, eller afledninger deraf. retninger; således fordybede han sig grundig i kemi ved Den polytekniske Læreanstalt. Det blev dog fornemmelig Paris, der fængslede ham. Han måtte bort fra det døde og til det levende, fra teori til praksis, og dette lykkedes ham, da .

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And so the whole– as the theory goes– the whole Earth essentially just iced over. And maybe we’ll look at the geological record, or the fossil record, and we’ll move these things around in the ret. Anything on the land would have just gotten irradiated.

Fysik – Kemi – Lys by Maria Danekilde on Prezi

And methane is an ozone– not an ozone. This is the greatest extinction event in Earth’s history, in History. So any of you Greeks out there, forgive me if I’m not getting the translation exactly right.

Now, the other interesting thing that happened– remember, we’re being bombarded with UV radiation from the Sun.

So what happened, and what I guess has to happen, and the reason why we are able to live on land now is that we have an ozone layer. And once it reacts with the oxygen and starts dropping out of the atmosphere as methane, we believe the Earth cooled down.


So it’s constantly being bombarded by with ultraviolet radiation from the Sun, which is very inhospitable to DNA and to life. And once it saturates, it starts to get released into the atmosphere. And that’s because the cyanobacteria is producing all this oxygen. So this kind of sets the stage for in the next eon, for animals or living things, to eventually get on to the land.


But this, as far as I can tell, deg our best current understanding. So this oxygen production, it’s crucial, one, to having an ozone layer so that eventually life can exist on the land.

Ozonlaget og eukaryoter dukker op i æonen Proterozoikum

So if you’re on the land– let me draw the land and the ocean. It’s possible that maybe life first started to exist at the end of the Hadeon Eon. But give or take a few hundred millions of years, one prokaryote got engulfed by another prokaryote, and said, hey, we do pretty well living together. And “UV” stands for ultraviolet. So that’s what they talk about right here on this diagram, the first snowball Earth.

The estimates are 50 to trillion eukaryotic cells.

But what happens is we enter into the Proterozoic Eon. So I’m drawing it in purple.

Ozonlaget og eukaryoter dukker op i æonen Proterozoikum (video) | Khan Academy

And the other big thing is now this is where the ozone forms. Now the other interesting thing, and we might not care so much about it because we needed the oxygen, is that we think that this was actually the greatest extinction event in the history of Earth. So as we go through the Proterozoic Eon, I guess the big markers of it is it’s the first time that we now have an oxygen-rich atmosphere.


And the Archean Eon is also the first eon where we still have rocks from that time. The first is is that it became suitable now for eukaryotes to exist. We’re made up of trillions. And I’ll do history with a capital H, in the history of the Earth.

It’s poisonous to most of the other organisms on the planet that were anaerobic, that did not need oxygen, that actually found oxygen poisonous. So here is the ocean and then here is the land. lveendes

It’s DNA would get mutated. I can only imagine that 50 years from now, or years from now, if someone is still watching this video, a lot of this might say, hey, we found out later that oxygen started to accumulate in the atmosphere earlier or later or that eukaryotes occurred earlier or later. It actually really reacts with the UV light to turn into ozone, which then can help actually block the UV light.

Oxygen dey in the atmosphere. And it’s the eon in which either life first started to exist or at least it first start to somewhat flourish.

So this right over here, 2. Here is the land, right over there in yellow, constantly being bombarded with UV radiation. And, of course, these dates, they might be moved around a few hundred million years as we get more and more data.