DNA is often purified by DNA electrophoresis, like in old-school DNA sequencing. In DNA electrophoresis, fragment separation is based on _____. (Best answer)
A.fragment charge.
B.fragment size.
C.fragment sequence.
D.fragment G-C content.
E. fragment A-T content.
The correct answer is B. fragment size. In DNA electrophoresis, the separation of DNA fragments is based on their size. The DNA molecules are subjected to an electric field, causing them to move through a gel matrix. Smaller fragments will move more quickly and thus migrate further through the gel compared to larger fragments. This allows for the separation of DNA fragments based on their size.
The correct answer is B. fragment size.
In DNA electrophoresis, the process relies on separating DNA fragments based on their size. This technique takes advantage of the fact that DNA is negatively charged due to the phosphate backbone, and when an electric field is applied, the DNA fragments migrate towards the positive electrode. However, smaller fragments move more easily through the gel matrix during the process, leading to their faster migration compared to larger fragments. This allows the separation of DNA fragments based on their size, with smaller fragments traveling further down the gel than larger ones. Consequently, the bands observed in the gel after electrophoresis represent different sizes of DNA fragments.