Final answer:
Proteins are separated in electrophoresis based on their charge and size. The direction and speed of protein movement depend on their charge, with positively charged proteins moving towards the anode and negatively charged proteins moving towards the cathode. Size also plays a role, with smaller proteins moving faster through the gel.
Step-by-step explanation:
Proteins are separated in electrophoresis on the basis of their charge and size. In gel electrophoresis, proteins with a net positive charge are attracted towards the negatively charged electrode (anode) and proteins with a net negative charge move towards the positively charged electrode (cathode). Furthermore, the proteins also separate based on their size, with smaller proteins moving faster through the gel than larger proteins.