Nearly every cell in a person’s body has the same DNA. Most of DNA is located in cell nucleus. We can say this DNA is like a stepladder and it can be as long as 1,80m but it can fold itself so tight it can be stored in a small space with micro dimensions.
Lets see how we can see this DNA without any microscopy help.
- 2 bowls, one of them must be transparent,
- a knife,
- a onion,
- dish detergent,
- 2 spoons,
- Peel the onion;
- Cut the onion, into small pieces, to the bowl;
- Add some dish detergent, enough to cover it;
- Add the salt (1/2 tablespoon);
- Finally add the water (2 tablespoons);
- Mix, careful, we don't want it to form bubbles;
- Wait 20 min;
- Mix again;
- Separate the liquid layer from the rest, the DNA is on the liquid, reject the rest.
- Add alcohol to the liquid, slowly, we want the alcohol to form a second layer above the liquid, try to make the alcohol run down the bowl wall.
- Don't mix the layers;
- Wait another 20 min.
You can see small white strands; some of them may look like small clusters.
DNA precipitates when mixed with alcohol; this means it's not soluble in this reagent. This causes the DNA to clump together when there is a lot of it. And, usually, cells contain a lot of it!
Salt- Helps DNA to precipitate
Cold water- Helps to maintain DNA intact. If we use hot water cellular enzymes can destroy the DNA strand.
Genetic in your kitchen!