Question

what is the principle behind the differential migration of molecules in gel electrophoresis?
a. the molecules all move at equal speed through the gel
b. the molecules move at different speeds through the gel according to their size
c. the molecules cant move through the gel and stay together.
d. the gel acts like a chemical knife and cuts the molecules into smaller pieces

Explanation:

Gel electrophoresis separates molecules. Smaller molecules move faster through the gel matrix than larger ones. Option A is incorrect as molecules don't move at equal speed. Option C is wrong because molecules do move. Option D is incorrect as the gel doesn't act as a chemical knife to cut molecules.

Answer:

B. The molecules move at different speeds through the gel according to their size