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Questions 1. Give two factors that influence the size of an individual\'s DNA fr

ID: 270394 • Letter: Q

Question

Questions 1. Give two factors that influence the size of an individual's DNA fragments after it Ih acted on by a restriction enzyme 2. The masses (sizes) of the four nucleotides in DNA are different-look them up. Why do those different masses not affect results of an agarose gel electrophoresis experiment? That is, suppose we had a 400 base-pair fragment composed of all A on one strand all T on the other strand. Why would that fragment travel the nearly same distance as a G-C 400 base- pair strand?

Explanation / Answer

The factors that affect the size of DNA when acted upon by the restriction enzyme include

1. Frequency of restriction sites: more the frequency of these sites, lesser will be the size of the fragments and vice versa

2. Activity of enzymes: more the active enzyme, more will it produce digestion products

3. Presence of enzymes like nucleases that cut the DNA non-specifically

4. Presence of inhibitors and other solvents like chloroform, ethanol etc