Two chromosomes.

It's fuckedup chromosomes.

The chromosomes line up.

It has two chromosomes.

It has 23 chromosomes.

I have 46 chromosomes.

It now has four chromosomes.

Humans usually have 46 chromosomes, two sets of 23, or simply 23 pairs of chromosomes.

You preserve the number of chromosomes.

The chromosomes line up during metaphase.

Cows have 30 pairs of chromosomes.

This is one of your chromosomes.

He gets split up into two chromatids, which we are now calling chromosomes, or sister chromosomes.

So diploid just means it has its full complement of chromosomes, so it has 2N chromosomes.

If I talked about other species, they might have 10 chromosomes or they might have 5 chromosomes.

Now, each cell only has two chromosomes.

We each have 23 pairs of chromosomes.

Haploid number for humans is 23 chromosomes.

different species have different numbers of chromosomes.

Rhesus monkeys have 21 pairs of chromosomes.

But we have 23 pairs of chromosomes.

So I'll draw my father's chromosomes in blue.

Then I have 23 chromosomes from my mother.

Now, these right here are called homologous chromosomes.

And on these chromosomes are roughly 25,000 genes.

It's got 2N chromosomes, and then it grows.

So S, you have replication of your chromosomes.

Potatoes, potatoes have 48 chromosomes. Do you know that?

And we'll come back to chromosomes in a minute.

In the mitosis video, I just had two chromosomes.

So you still have a diploid number of chromosomes.

As it goes through S phase, these chromosomes replicate.

And you have your two chromosomes in this case.

literally just means half the normal group of chromosomes.

In practice they don't test people for their chromosomes.

And that's actually just in half of your chromosomes.

We control their chromosomes. It's really not that difficult.

The way I suspect it will happen is using artificial chromosomes and extra chromosomes, so we go from 46 to 47 or 48.

It is obviously central to the movement of the chromosomes.

Now, in prophase, that starts to form into the chromosomes.

Let's see, so I have 23 chromosomes from my mother.

Chromosome one top left, bottom right are the sex chromosomes.

And just like in mitosis, as soon as the sister chromatids are split apart, they are now referred to as chromosomes, or sister chromosomes.

So if you started off with 43 chromosomes, formally have 23 chromosomes in each one, or you can almost view it if you have 23 pairs here, each have two chromosomes, those pairs get split into this stage.

And S is where you have replication of the actual chromosomes.