Question

During the process of isolation of DNA, chilled ethanol is added to

• A. Break open the cell to release DNA
• B. Facilitate action of restriction enzymes
• C. Remove proteins such as histones
• D. Precipitate DNA

Answer 1

Answer: (D)

Precipitate DNA

It is well known that Ethanol has a lower dielectric constant than water, making it promote ionic bond formations the $N{a}^{+}$ (from the salt) and the $P{O}^{3-}$ (from the DNA backbone), further, causing the DNA to precipitate.

So the correct answer is option D.