Question

The part of a gel where samples are loaded is often called the "top" of the gel; the opposite end of the gel is then referred to as the "bottom" of the gel. After electrophoresis is complete, where will the smallest DNA fragments be found?

Answer 1

The smallest DNA fragments will be located at the bottom of the gel after electrophoresis because they travel farther than larger fragments through the molecular sieve.

Step-by-step explanation:

After electrophoresis is complete, the smallest DNA fragments will be found at the bottom of the gel, which is the end opposite to where the samples are initially loaded. These smaller fragments travel farther through the agarose gel matrix due to their size; they are less impeded by the molecular sieve than larger fragments. Thus, across the gel, the distance of migration is inversely correlated to the size of the DNA fragment.