Question

Dna molecules have a ________ charge and therefore move toward the _________ electrode.

a) positive; positive
b) negative; negative
c) negative; positive
d) positive; negative

Answer 1

DNA molecules carry a negative charge and are drawn towards the positive electrode when subjected to an electric field, such as during gel electrophoresis.

Step-by-step explanation:

DNA molecules have a negative charge due to the phosphate backbone, and therefore, they move toward the positive electrode during techniques such as gel electrophoresis. The correct response to the question is: DNA molecules have a negative charge and therefore move toward the positive electrode. Therefore, the answer is c) negative; positive.

Within an electric field, negatively charged particles will move towards regions of higher potential, meaning they are attracted to the positive electrode. This principle underlies many biochemical procedures, providing the basis for separating DNA fragments by size during gel electrophoresis. Smaller DNA molecules will move through the gel more quickly, allowing for the sorting of DNA strands according to their length.