Multiple Choice Questions and Answers on Gel Electrophoresis
Question 1 : In a gel filtration column
- smaller proteins enter the beads more readily
- large proteins elute first
- both (1) and (2)
- large proteins enter the beads more readily
Answer : 3
Question 2 : In a native PAGE, proteins are separated on the basis of
- net negative charge
- net charge and size
- net positive charges size
- net positive charge
Answer : 2
Question 3 : The subunit molecular weight as well as the number of subunits in the quaternary structure can be determined by
- SDS-PAGE electrophoresis
- gel filtration chromatography
- combining information from (1)and (2)
- isoelectric focusing
Answer : 3
Question 4 : Proteins are separated in an SDS-PAGE experiment on the basis of their
- positively charged side chains
- molecular weight
- negatively charged side chains
- different isoelectric points
Answer : 2
Question 5 : In an SDS-PAGE
- proteins are denatured by the SDS
- proteins have the same charge-to-mass ratio
- smaller proteins migrate more rapidly through the gel
- all of the above
Answer : 4
Question 6 : Proteins can be visualized directly in gels by
- staining them with the dye
- using electron microscope only
- measuring their molecular weight
- none of these
Answer : 1
Question 7 : In SDS-PAGE, the protein sample is first
- treated with a reducing agent and then with anionic detergent followed by fractionation by electrophoresis
- fractionated by electrophoresis then treated with an oxidizing agent followed by anionic detergent.
- treated with a oxidizing agent and then with anionic detergent followed by fractionation by electrophoresis
- none of the above
Answer : 1
Question 8 : Electrophoresis of histones and myoglobin under non-denaturing conditions (pH = 7.0) results in
- both proteins migrate to the anode
- histones migrate to the anode and myoglobin migrates to the cathode
- histones migrate to the cathode and myoglobin migrates to the anode
- both proteins migrate to the cathode
Answer : 3
Question 9 : In isoelectric focusing, proteins are separated on the basis of their
- relative content of positively charged residue only
- relative content of negatively charged residue only
- size
- relative content of positively and negatively charged residue
Answer : 4