What is gel electrophoresis
ANSWER
the separation of materials based on size and migration patterns when subjected to electri-
cal forces in a resistive medium.
What are the 3 types of gel electrophoresis
ANSWER
Agarose
Polyacrylamide
Pulse Field
which direction does the DNA flow in gel electrophoresis
ANSWER
due to DNA being negatively charged, it will migrate towards the positive end
What determines how far the DNA will travel in a gel
ANSWER
the size of the DNA fragment
What factors affect migration of smaples within a gel
ANSWER
buffer concentrations
gel make up
physical factors
1
,time
electric current
What is agarose gel electrophoresis
ANSWER
most common gel- polysaccharide extracted from seaweed- concentrations are varied with
the size of DNA trying to be separated
larger DNA size = lower concentrations of agar (.5%=1%)
smaller DNA size = higher concentrations (2%-3%)
What is Polyacrylamide gel electrophoresis
ANSWER
used for the resolution of very small DNA segments (PAGE). Can detect 1bp differences in
segments.
Is chemically prepared and catalyzed into the gel
Pore size is easily adjusted during gel preparation for custom gels to particular experiments
What is Pulse Field Gel Electrophoresis
ANSWER
for resolution of ver large pieces of DNA 50k +
Along with specific gel and buffer combinations the electrical field is pulsed or alternated in
various directions/dimensions to facilitate movement of large pieces
Fled inversion gel electrophoresis is the most common PFGE and is achieved by switching
the anode and cathode periodically for repeated forward and back movements of the frag-
ments to gain resolutions.
Variations occur at 90 deg to normal electron flow, in circular patterns
what is capillary electrophoresis
ANSWER
2
, mostly used for the separation of chemicals and multicompound molecules.
Describe capillary electrophoresis
ANSWER
A sample is dissolved in buffer
Buffer systems are charge dand connected via a glass capillary
smaller negatively charged objects travel faster than large positive charged ones.
Fluorescent light is sent through a window in the capillary and a detector measures absorb-
ance as objects pass
When used for nucleicc acid the DNA must be completely denatured (single stranded) the
capillary is held at denaturing temperatures and dissipates heat well
Very small volumes of DNA and when subjected to high currents the small fragments are de-
tected first
What are the types of blotting
ANSWER
Southern blot
Northern Blot
Western blot
Southwestern Bot
Eastern Blot
Far Eastern blot
Describe a northern blot
ANSWER
Target: RNA
Probe: Nucleic Acid
Purpose: Transcript structure, processing, gene expression
3
ANSWER
the separation of materials based on size and migration patterns when subjected to electri-
cal forces in a resistive medium.
What are the 3 types of gel electrophoresis
ANSWER
Agarose
Polyacrylamide
Pulse Field
which direction does the DNA flow in gel electrophoresis
ANSWER
due to DNA being negatively charged, it will migrate towards the positive end
What determines how far the DNA will travel in a gel
ANSWER
the size of the DNA fragment
What factors affect migration of smaples within a gel
ANSWER
buffer concentrations
gel make up
physical factors
1
,time
electric current
What is agarose gel electrophoresis
ANSWER
most common gel- polysaccharide extracted from seaweed- concentrations are varied with
the size of DNA trying to be separated
larger DNA size = lower concentrations of agar (.5%=1%)
smaller DNA size = higher concentrations (2%-3%)
What is Polyacrylamide gel electrophoresis
ANSWER
used for the resolution of very small DNA segments (PAGE). Can detect 1bp differences in
segments.
Is chemically prepared and catalyzed into the gel
Pore size is easily adjusted during gel preparation for custom gels to particular experiments
What is Pulse Field Gel Electrophoresis
ANSWER
for resolution of ver large pieces of DNA 50k +
Along with specific gel and buffer combinations the electrical field is pulsed or alternated in
various directions/dimensions to facilitate movement of large pieces
Fled inversion gel electrophoresis is the most common PFGE and is achieved by switching
the anode and cathode periodically for repeated forward and back movements of the frag-
ments to gain resolutions.
Variations occur at 90 deg to normal electron flow, in circular patterns
what is capillary electrophoresis
ANSWER
2
, mostly used for the separation of chemicals and multicompound molecules.
Describe capillary electrophoresis
ANSWER
A sample is dissolved in buffer
Buffer systems are charge dand connected via a glass capillary
smaller negatively charged objects travel faster than large positive charged ones.
Fluorescent light is sent through a window in the capillary and a detector measures absorb-
ance as objects pass
When used for nucleicc acid the DNA must be completely denatured (single stranded) the
capillary is held at denaturing temperatures and dissipates heat well
Very small volumes of DNA and when subjected to high currents the small fragments are de-
tected first
What are the types of blotting
ANSWER
Southern blot
Northern Blot
Western blot
Southwestern Bot
Eastern Blot
Far Eastern blot
Describe a northern blot
ANSWER
Target: RNA
Probe: Nucleic Acid
Purpose: Transcript structure, processing, gene expression
3
