Why do smaller DNA fragments travel farther than larger fragments during gel electrophoresis?

Correct answer: Smaller fragments pass through the gel pores more easily

DNA fragments carry a negative electrical charge, so all of them move toward the positive electrode in an electric field. The porous gel matrix hinders larger fragments more strongly, whereas smaller fragments pass through its pores more easily and travel farther. Therefore, option B is incorrect because both small and large DNA fragments are charged. Exam tip: Under the same conditions, the DNA band that travels farther is generally the smaller fragment.