KCET 2016 Biology Solved Paper

Gel electrophoresis is a technique that uses differences in electrical charges to separate the molecules in a mixture. Since DNA molecules have negative charges, they migrate towards the positive electrode (anode) when placed in an electric field. This rate of migration depends on size. The smaller the DNA molecule, faster is the migration. So, the DNA band that is the farthest from the well where it was loaded, is the smallest in size.