MCAT Lab Techniques Questions with Detailed Verified Answers

Page | 1



MCAT Lab Techniques Questions with
Detailed Verified Answers
Question: gel electrophoresis
Answer: separates DNA fragments by size


Question:
What is Electrophoresis
Answer: uses an electrical field to move DNA or RNA molecules through a
medium (gel) based on size/charge


Question:
What happens to shorter DNA fragments in electrophoresis?
Answer: Migrate through gel quicker


Question:
Which moves faster in gel electrophoresis: positively charged or negatively
charged molecules?
Answer: negatively charged molecules due to attraction to positive anode


Question:
agarose gel electrophoresis
Answer: uses agarose gel which is more effective for larger DNA molecules


Question:
Native PAGE (polyacrylamide gel electrophoresis)

, Page | 2

Answer: Analyzes proteins in their native states.
Maintains protein structure and shape


Question:
When is it useful to use native PAGE?
Answer: When comparing molecular size/charge of proteins known to be
similar in size


Question:
SDS-PAGE electrophoresis
Answer: separates proteins based on molecular mass
-denatures proteins through addition of detergent which disrupts non-
covalent interactions


Question:
Isoelectric Focusing
Answer: separates proteins by their isoelectric point (pI); the protein migrates
toward an electrode until it reaches a region of the gel where pH=pI of the
protein


Question:
Chromatography
Answer: A technique that is used to separate the components of a mixture
based on the tendency of each component to travel or be drawn across the
surface of another material.


Question: