Why are the proteins being separated on an SDS polyacrylamide gel attracted equally to the positive electrode?
A)They carry a relatively uniform positive charge distribution
B)They carry a relatively uniform negative charge distribution.
C)They are all the same molecular weight.
D)They are all the same size.
E)They all have the same degree of hydrophobicity.

Question

Quizplus · Accepted Answer

SDS (sodium dodecyl sulfate) is a negatively charged detergent that binds to proteins in a stoichiometric manner, such that each protein molecule binds a fixed amount of SDS per unit weight, giving it a uniformly negative charge. Therefore, in an SDS-PAGE gel, all the proteins would have a relatively uniform negative charge distribution and would be attracted equally to the positively charged electrode.

Why Are the Proteins Being Separated on an SDS Polyacrylamide