Biotech Gel Electrophoresis: Questions & Answers
What is electrophoresis? Right Ans - The migration of charged particles
under the influence of an electric field
What does electro mean? Right Ans - electricity
What does phoresis mean? Right Ans - "to carry across"
What is electrophoretic mobility? Right Ans - ratio of electrical force to
frictional force
What is gel electrophoresis? Right Ans - A method that separates
macromolecules (either nucleic acids or proteins) on the basis of size
How does gel electrophoresis work? Right Ans - Molecules are forced
across a span of gel. Electrodes at either end of the gel provide the driving
force.
The charged particles migrate either to the cathode or to the anode.
What determines how rapidly a molecule moves through a gelatinous medium
in gel electrophoresis? Right Ans - the size of the molecule
Many important biological molecules posses _____ and therefore at any given
pH exist in solution as what? Right Ans - ionizable groups and exist in
solution as electrically charged species either as cations (+) or anions (-)
Separation of large (macro) molecules depends upon what two forces?
Right Ans - charge and mass
What is the role of the electric field? Right Ans - repels the molecules from
one electrode while the other electrode simultaneously attracts the molecules
What does the pore size of the gel act as? Right Ans - a "molecular sieve"
separating the molecules by size
, What happens when charged molecules are placed in an electric field?
Right Ans - They migrate toward either the positive (anode) or negative
(cathode) pole
What charge do nucleic acids have and why? Right Ans - consistent
negative charge imparted by their phosphate backbone
Where do nucleic acids migrate toward? Right Ans - migrate toward the
anode
Sodium dodecyl sulphate (SDS) is an anionic detergent which denatures
proteins how?
What does this result in ? Right Ans - by "wrapping around" the
polypeptide backbone
this results in the peptide having an overall negative charge
The charge to mass ratio is _____ in DNA Right Ans - constant
What are involved in forming covalent bonds in ssDNA? Right Ans - sugars
What are the types of gel electrophoresis? Right Ans - agarose and
polyacrylamide
Where does agarose originate? Right Ans - a natural colloid extract from
seaweed
Is agarose fragile? Right Ans - yes, easily destroyed by handling
How big is the pore size in agarose gel? What is agarose gel primarily used
for? Right Ans - very large pore size and used primarily to separate very
large molecules with a molecular mass greater than 200kdal
Which gel can be processed faster? Right Ans - agarose, but resolution is
inferior
Which gel has bands formed that are fuzzy and spread far apart
Why? Right Ans - agarose
result of pore size and can't be controlled
What is electrophoresis? Right Ans - The migration of charged particles
under the influence of an electric field
What does electro mean? Right Ans - electricity
What does phoresis mean? Right Ans - "to carry across"
What is electrophoretic mobility? Right Ans - ratio of electrical force to
frictional force
What is gel electrophoresis? Right Ans - A method that separates
macromolecules (either nucleic acids or proteins) on the basis of size
How does gel electrophoresis work? Right Ans - Molecules are forced
across a span of gel. Electrodes at either end of the gel provide the driving
force.
The charged particles migrate either to the cathode or to the anode.
What determines how rapidly a molecule moves through a gelatinous medium
in gel electrophoresis? Right Ans - the size of the molecule
Many important biological molecules posses _____ and therefore at any given
pH exist in solution as what? Right Ans - ionizable groups and exist in
solution as electrically charged species either as cations (+) or anions (-)
Separation of large (macro) molecules depends upon what two forces?
Right Ans - charge and mass
What is the role of the electric field? Right Ans - repels the molecules from
one electrode while the other electrode simultaneously attracts the molecules
What does the pore size of the gel act as? Right Ans - a "molecular sieve"
separating the molecules by size
, What happens when charged molecules are placed in an electric field?
Right Ans - They migrate toward either the positive (anode) or negative
(cathode) pole
What charge do nucleic acids have and why? Right Ans - consistent
negative charge imparted by their phosphate backbone
Where do nucleic acids migrate toward? Right Ans - migrate toward the
anode
Sodium dodecyl sulphate (SDS) is an anionic detergent which denatures
proteins how?
What does this result in ? Right Ans - by "wrapping around" the
polypeptide backbone
this results in the peptide having an overall negative charge
The charge to mass ratio is _____ in DNA Right Ans - constant
What are involved in forming covalent bonds in ssDNA? Right Ans - sugars
What are the types of gel electrophoresis? Right Ans - agarose and
polyacrylamide
Where does agarose originate? Right Ans - a natural colloid extract from
seaweed
Is agarose fragile? Right Ans - yes, easily destroyed by handling
How big is the pore size in agarose gel? What is agarose gel primarily used
for? Right Ans - very large pore size and used primarily to separate very
large molecules with a molecular mass greater than 200kdal
Which gel can be processed faster? Right Ans - agarose, but resolution is
inferior
Which gel has bands formed that are fuzzy and spread far apart
Why? Right Ans - agarose
result of pore size and can't be controlled
