Question

Which of the following sequences would run the slowest through an agarose gel during gel electrophoresis?

a) 5'- AT -3'

b) 5’- ATGCTGC -3’

c) 5’- ATGCTGCAGTTA -3'

d) All of these sequences would run at the same speed

Answer 1

ANSWER: OPTION- C [5’- ATGCTGCAGTTA -3']

Explanation:

Agarose gel electrophoresis is a technique by which we can separate DNA fragments on the basis of their molecular weight (size). The DNA is negatively charged so while doing electrophoresis when an electric current is applied then the DNA starts to move towards the positive electrode. The DNA fragment with smallest size will move faster and farthest while the DNA fragments with largest size will moves slower.

So here 5’- ATGCTGCAGTTA -3' moves slowest and 5'- AT -3' will moves fastest.