The following figure shows that gel electrophoresis can be used to separate repetitive DNA sequences. Gel electrophoresis separates DNA fragments because ______.
A) double stranded moves slower than single stranded DNA
B) of ratios of guanine to cytosine
C) the DNA fragments have different lengths
D) of the salt concentration in the gel matrix

Question

The following figure shows that gel electrophoresis can be used to separate repetitive DNA sequences. Gel electrophoresis separates DNA fragments because ______. 
A) double stranded moves slower than single stranded DNA 
B) of ratios of guanine to cytosine 
C) the DNA fragments have different lengths 
D) of the salt concentration in the gel matrix

Quizplus · Accepted Answer

Gel electrophoresis separates DNA fragments based on their size. As repetitive DNA sequences will have different fragment sizes, they can be separated using gel electrophoresis. Choice A is incorrect as both double stranded and single stranded DNA fragments move at the same rate. Choice B is incorrect as the ratio of guanine to cytosine will not affect the size of the DNA fragments. Choice D is incorrect as salt concentration affects the migration rate of DNA fragments, but is not the main factor in separating DNA fragments by size.

The Following Figure Shows That Gel Electrophoresis Can Be Used