If we look at prokaryotic chromosomes it's different.

如果我们观察原核生物的染体，情况就不同了。

A lot of ancient fossils contain evidence of prokaryotic life, like bacteria.

许多古代化石含有原核生物，如细菌的证据。

There is the eukaryotic strategy and the prokaryotic strategy.

这里有真核策略和原核策略。

Did they have a dimorphism between prokaryotic, eukaryotic?

它们在原核生物和真核生物之间是否存在二态性？

In a prokaryotic chromosome, the chromosome is simply loose here.

在原核生物染体, 染体在这里只是松散的。

But know that cells can be prokaryotic or eukaryotic.

但要知道，细胞可以是原核的或真核的。

But in prokaryotics they've got just a loop.

但在原核生物, 它们只有一个。

And each one of those has a probability of one in 1,000, to go from eukaryotic, prokaryotic, whatever.

每一个障碍的概率都是千分之一，无论是从真核生物到原核生物，还是他任何情况。

Prokaryotic cells, so things like bacteria and archaea are going to be on the order of about a micrometer.

原核细胞，比如细菌和古菌的大小大约在微米级别。

Two types of prokaryotic cells are bacteria and archaea.

两种原核细胞是细菌和古菌。

The cDNAs had to be linked to prokaryotic transcription and translation signals and inserted into multicopy plasmids.

然而，占总蛋白30%的过量表达的蛋白质是沉淀或不溶的形式并且缺少翻译后修饰。

So this is going to be prokaryotic life.

所以这将是原核生物生命。

And so we can date that rock and figure out that first life started about 3.8 billion years ago but it's prokaryotic.

因此我们可以测定那块岩石的年龄，推断出最初的生命大约在38亿年前开始出现，但它们是原核生物。

Alright, as a quick recap, the bacteria are prokaryotic cells that play an important role in human disease and health and can be found almost anywhere in the environment.

得！快速回顾一下：细菌是一种在人类健康与疾病发生有重要作用的原核细胞，在我们生活的境无处不在。

On the other hand, prokaryotic organisms like bacteria lack organelles, so their cellular contents are a little more willy-nilly, like that junk drawer where you keep the chip clips and sauce packets.

另一方面，像细菌这样的原核生物缺乏细胞器，所以它们的细胞内容物有点杂乱无章，就像你放薯片夹和酱包的垃圾抽屉一样。

And if you look at the DNA of a prokaryotic cell, each of those little stretches is going to be one gene after gene after gene after gene.

如果你观察原核细胞的 DNA，你会发现每一个小片段都对应着一个又一个基因。

But there is this transition from no oxygen to oxygen, from prokaryotic life to eukaryotic life, from single cell to multi-cell, to the arrival of animals, plants and then this movement, eventually, on to land.

但从无氧到有氧，从原核生物到真核生物，从单细胞到多细胞，再到动物和植物的出现，最终迁移到陆地上。