First one is crossing over during meiosis.

第一个减数分裂期间的染色体交叉互换。

On top of, and here we also see crossing over occurring right there.

此外，我们还可以看到染色体交叉互换正在此处发。

To put it simply, during meiosis, the process in which gametes[3] are created, chromosomal crossover occurs.

而言之，在减数分裂过程中， 即产配子 [3] 的过程中，会发染色体交叉。

And this first one would be crossing over.

第一个机制染色体交叉互换。

This is when an individual's chromosomes, which are are inherited from each of the parents, cross over one another, enabling genes from one chromosome to swap places with genes from another.

从每个父母那里继承的个体染色体相互交叉时，使一个染色体的基因能够与另一个染色体的基因交换位置。

But if we didn't have crossing over, all the genes that are found on that one chromosome, which is you know hundreds of genes, would just kind of travel together through time.

但如果我们没有染色体交叉互换，那么位于同一条染色体上的所有基因，你知道的， 有数百个基因，就会随着时间的推移而一起移动。

And in crossing over what happens is the homologous chromosomes, in other words the chromosome from dad and the chromosome from mom, will actually wrap around each other and they'll share some of that information.

在染色体交叉互换过程中， 同源染色体，也就来自父亲的染色体和来自母亲的染色体，会实际缠绕在一起并交换部分信息。