Biochemistry - Lab Techniques Flashcards
What is the purpose of using DNA polymerase chain reaction?
To amplify the number of copies of DNA fragments
How is the size of a DNA fragment determined from an agarose gel?
A DNA ladder of known lengths is run alongside the polymerase chain reaction fragments
How is DNA separated into two strands during polymerase chain reaction?
By heating
In polymerase chain reaction, premade _____ are used to anneal to specific DNA sequences that will then be amplified.
Primers
What enzyme is used in polymerase chain reaction to amplify DNA?
Heat-stable DNA polymerase
What are the three steps of DNA polymerase chain reaction in order?
Denaturation, annealing, elongation
What is the advantage of using a heat-stable DNA polymerase?
The polymerase is not denatured by heating and can be reused for multiple cycles of polymerase chain reaction
Following PCR, how can products be separated and analyzed?
Agarose gel electrophoresis
Which would travel further on an agarose gel: a 10-kD or an 100-kD DNA fragment?
The 10-kD fragment; smaller molecules travel further
Describe the technique of a Western blot.
Sample protein is separated via gel electrophoresis and transferred to a filter; labeled antibody is used to bind the protein of interest
What blot technique detects specific sequences of DNA?
Southern blot
How does the mnemonic “SNoW DRoP” help one remember which type of blot is used to detect DNA sequences, RNA sequences, or proteins?
Southern = DNA, Northern = RNA, Western = Protein
Describe the technique of a Southern blot.
DNA is run on an electrophoresis gel and transferred to a filter; the DNA on the filter is denatured and exposed to a labeled DNA probe, and then the double-stranded DNA is visualized when the filter is exposed to film
Describe the technique of a Northern blot.
RNA is run on an electrophoresis gel and transferred to a filter; the RNA on the filter is exposed to a labelled DNA probe, and then the hybrid DNA-RNA molecule is visualized when the filter is exposed to film
Which assay would allow you to detect single nucleotide polymorphisms?
Microarrays
How can a microarray profile gene expression levels?
The microarray scanner can detect relative amounts of complementary binding to probes
Describe the technique of using a microarray to detect gene expression levels
Thousands of nucleic acid sequences are arranged in grids on glass or silicon. DNA or RNA probes are hybridized to the chip, and a scanner detects the relative amounts of complementary binding
True or False? In the microarray biology technique, DNA or RNA probes are hybridized to the chip.
True; either DNA or RNA probes may be used