Extracting DNA

Question 1

What is the role of salt in the extracting DNA practical?

Answer 1

The salt will cause the DNA to clump together, which will make it easier to precipitate

Question 2

What is the role of detergent in the extracting DNA practical?

Answer 2

Breaks down and dissolves the cell-surface membrane and the nuclear membrane

Question 3

What is the role of protease in the extracting DNA practical?

Answer 3

Breaks down the histone proteins which the DNA is coiled around

Question 4

What is the role of ethanol in the extracting DNA practical?

Answer 4

DNA is insoluble in ethanol. This causes the DNA to clump together and precipitate, making it visible

Question 5

Why might you keep the food solution with the salt, detergent and protease in a water bath for 1 minutes?

Answer 5

It will allow it to reach optimum temperature for the protease which will speed up the rate of reaction