ch.6 Flashcards
What component of a PCR reaction is labeled with a fluorescent dye to enable detection of amplified STR alleles?
The primer is labeled, which is an oligonucleotide that is flourescently labeled and will attach onto its specific target sequence.
What is electro-osmotic flow and how does it impact DNA separations in a capillary?
Electro-osmotic flow is the motion of liquid induced by an applied potential.
Small, highly charged DNA/ions will move through the capillary the fastest.
In DNA, as size increases, so does charge.
A DNA profile is produced by Separating ..
DNA molecules by size and dye color
Fragment sizes range from __ - ___ base pairs
100,300
labeled fragments are separated based on __ and detected on a __ , this takes about ~ ___
size
gel electrophoresis instrument
2 hours or less
the polymerase chain reaction is used to ..
amplify STR regions and label the amplicons with fluorescent dyes using locus- specific primers
steps of capillary electrophoresis
- narrow glass capillary
- two buffer vials
- two electrodes with high power supply
- capillary has one lane of agarose, while DNA is injected with size standards
- laser light is shined in a window & DNA is illuminated as it passes by
for CE , how do the dna molecules move more through the capillary
slowly
disadvantages of capillary electrophoresis
high start up cost of gels
labor intensive
hazardous chemicals
advantages of capillary electrophoresis
automated
small amounts can be loaded
available software
separation happens in minutes instead of hours
what makes agarose
form of seaweed, mix with buffer, heat, pour in gel box
how can you visualize DNA (with agarose gel electrophoresis)
UV
are the polyacrylamide polymer pores bigger or smaller than agarose
smaller
what was used to help denature
formamide and urea (separate s strands)
* also temperature and pH was used*
what are the different separations
electrophoresis
slap gel : polyacrylamide , agarose
capillary
