PASS Week 3 Review

Which of the following is the primary purpose of SDS in SDS-PAGE?

• To break disulfide bonds

• To denature proteins and give them a uniform negative charge

• To separate proteins based on their isoelectric point

• To visualize protein bands with Coomassie stain

Isoelectric focusing separates proteins based on their:

• Size

• Charge-to-mass ratio

• Hydrophobicity

• Isoelectric point (pI)

What is the main advantage of 2D gel electrophoresis compared to single-dimension techniques?

• It requires less sample preparation

• It separates proteins based on both charge and size

• It uses fewer reagents

• It is faster than SDS-PAGE

Edman degradation is used for:

• Determining the 3D structure of proteins

• Sequencing amino acids from the N-terminus of a protein

• Isolating proteins based on size

• Visualizing proteins on a gel

Which antibody-based detection method is most suitable for detecting low abundance proteins?

• Chromogenic

• Chemiluminescent

• Fluorometric

• Colorimetric

Which technique does not require protein crystallization for structure determination?

• X-ray crystallography

• Protein NMR

• CryoEM

• Both B and C

What type of chromatography separates proteins based on their charge?

• Gel filtration

• Ion exchange

• Affinity

• Reverse-phase

What is the primary role of enzymes in biological reactions?

• To decrease the free energy of the reaction

• To increase the free energy of activation

• To catalyze reactions and increase the reaction rate

• To change the equilibrium of the reaction

Enzyme names typically end with which suffix?

• -ase

• -ose

• -ine

• -ate

Which type of molecule can act as a cofactor for enzymes?

• Carbohydrates

• Lipids

• Inorganic ions

• Nucleic acids