Answer:
B. Electrophoresis separates molecules based on charge differences, thereby making it possible to separate molecules that are similar in size, shape, and density.
Explanation:
Chromatography is a process that is used for the separation of complex mixtures of molecules by many repeated partitioning between a flowing (mobile) phase and a stationary phase. The process exploits the properties of the molecules such as charge, size, binding affinity, etc.
However, gel electrophoresis is the technique that separates the molecules based on their charge or mass. It can separate a mixture of molecules with a similar charge based on their mass. Likewise, if all the molecules of a mixture have the same mass but differ in charge, gel electrophoresis can be used to separate them based on their different charges.
For example, a mixture of proteins is allowed to run through the gel of cross-linked polymer polyacrylamide under electrical potential towards the positive or negative electrode. The polyacrylamide gel serves as a sieve and allows the proteins to migrate in proportion to the charge to mass ratio. If all the proteins are of the same mass, gel electrophoresis would separate them based on their charge.
