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MCAT Lab Techniques Questions with Answers (100%
Correct Answers)
gel electrophoresis Answer: separates DNA fragments by size
What is Electrophoresis Answer: uses an electrical field to move DNA
or RNA molecules through a medium (gel) based on size/charge
What happens to shorter DNA fragments in electrophoresis? Answer:
Migrate through gel quicker
Which moves faster in gel electrophoresis: positively charged or
negatively charged molecules? Answer: negatively charged molecules
due to attraction to positive anode
agarose gel electrophoresis Answer: uses agarose gel which is more
effective for larger DNA molecules
Native PAGE (polyacrylamide gel electrophoresis) Answer: Analyzes
proteins in their native states.
Maintains protein structure and shape
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When is it useful to use native PAGE? Answer: When comparing
molecular size/charge of proteins known to be similar in size
SDS-PAGE electrophoresis Answer: separates proteins based on
molecular mass
-denatures proteins through addition of detergent which disrupts non-
covalent interactions
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
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.
Retention Time Answer: amount of time a compound spends in
stationary phase
in normal phase chromatography: what polarity is the stationary
phase? Answer: polar
in normal phase chromatography: what polarity is the mobil phase?
Answer: nonpolar
© 2025 All rights reserved
MCAT Lab Techniques Questions with Answers (100%
Correct Answers)
gel electrophoresis Answer: separates DNA fragments by size
What is Electrophoresis Answer: uses an electrical field to move DNA
or RNA molecules through a medium (gel) based on size/charge
What happens to shorter DNA fragments in electrophoresis? Answer:
Migrate through gel quicker
Which moves faster in gel electrophoresis: positively charged or
negatively charged molecules? Answer: negatively charged molecules
due to attraction to positive anode
agarose gel electrophoresis Answer: uses agarose gel which is more
effective for larger DNA molecules
Native PAGE (polyacrylamide gel electrophoresis) Answer: Analyzes
proteins in their native states.
Maintains protein structure and shape
© 2025 All rights reserved
, 2
When is it useful to use native PAGE? Answer: When comparing
molecular size/charge of proteins known to be similar in size
SDS-PAGE electrophoresis Answer: separates proteins based on
molecular mass
-denatures proteins through addition of detergent which disrupts non-
covalent interactions
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
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.
Retention Time Answer: amount of time a compound spends in
stationary phase
in normal phase chromatography: what polarity is the stationary
phase? Answer: polar
in normal phase chromatography: what polarity is the mobil phase?
Answer: nonpolar
© 2025 All rights reserved
