00:02
This question asks us to explain the principle behind using gel electrophoresis to determine the concentration and quality of an isolated dna.
00:14
So we know that with gel electrophoresis, we have a gel.
00:23
We have these wells on our gel that we'll have up here.
00:29
So this would be like in the gel.
00:31
It would be these slots.
00:36
Basically, you'd be able to make this by putting in a special comb that, would sit in these slots when you pour this gel.
00:45
So the gel would harden, and once you pull the comb out, it will leave these indentations in the gel into which you can load your sample.
00:53
So your sample would be like in the little tube, and you'd be able to load your dna sample into these wells.
01:03
So once you've loaded your dna sample into the wells, you can run this dna, you can run your samples out on the electrophoree.
01:11
So what is the basis behind this? well, we're going to have, on this end, a wire, essentially, in the solution, and there will be an electric current that flows.
01:28
So because of this negative charge here, and because dna is positively charged, so this is positively charged, it will be attracted to the negative.
01:38
So we'll have a flow of this dna to our negative electrode.
01:46
So this is what's going to drive the dna to the bottom of the gel.
01:55
Now, the principle behind gelal electrophoresis is that we're separating based on size of our dna molecule.
02:03
So based on the length of our dna sequence, it will travel a different distance in a given amount of time.
02:10
So it's a short sequence.
02:13
So we'll say short is right here...