Protein Analysis

What does SDS-PAGE stand for?

• Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis

• Single-Stranded DNA Polymerase Gel Electrophoresis

• Serum-Derived Stem-Platelet Aggregation Electrophoresis

• Standard Differential Staining-Photoelectric Gel Electrophoresis

In SDS-PAGE, what is the role of SDS?

• Breaks disulphide bonds

• Imparts a negative charge

• It denatures proteins

• Enhances protein movement through the gel

What is the purpose of polyacrylamide in SDS-PAGE?

• Provides structural support for proteins

• To separate proteins by size

• To facilitate protein denaturation

• To enhance protein staining

What is the primary factor that determines the migration of proteins ins SDS-PAGE

• Charge

• Size

• Shape

• Hydrophobicity

How is the molecular weight of proteins determined in SDS-PAGE?

• By the intensity of staining

• By comparing the sample to known molecular weight markers

• Calculations using the gel percentage, voltage, and time

• Luck

What is the purpose of the stacking gel in SDS-PAGE?

• To provide a platform for sample loading

• To separate proteins based on size

• To concentrate proteins in a narrow band so they enter the resolving gel at the same time

• To enhance protein denaturation

What is the purpose of the reducing agent in SDS-PAGE sample preparation

• To give the protein a net negative charge

• To improve protein solubility

• To reduce disulphide bonds

• To improve protein transfer

What is the first stage in the western blotting procedure?

• Transfer

• Electrophoresis

• Blocking

• Antibody Incubation

In western blotting what is the purpose of the blocking step?

• To amplify signal intensity

• To aid antibody binding

• To prevent nonspecific binding of antibodies

• To aid in protein visualisation

What is the purpose of a secondary antibody in western blotting?

• To block nonspecific binding

• To enhance signal intensity

• To directly bind the target protein

• To separate proteins by size