we are going to use the blood sample you collected at the crime scene. what needs to happen before the blood sample can be used for PCR?
DNA has to be
... [Show More] isolated from the cells
what do you need to do each time before using a pipette to collect liquid?
put on a new, sterile pipette tip
why is it important to change the pipette tip?
to avoid cross contamination
how did you collect liquid in the lab?
using a pipette
what is the template of the PCR?
DNA
for which enzyme are nucleotides the substrate?
DNA polymerase
what does a DNA polymerase do?
synthesizes DNA
at this step in the PCR process, what happens to the DNA?
it will be separated into two strands
how is the DNA separated into single strands?
the high temperature (95C)
what is the step in the PCR that is now shown called?
annealing
the area where the primers bind marks which part of the PCR product?
beginning
the PCR products get a certain length due to which fact?
the placement of the primers
how does the DNA polymerase extend the primers into a new DNA strand?
adding nucleotides to the 3' end of the primers
primers are always designed to be complementary to the template DNA strand. which of these sequences is the complementary sequence to the template sequence:
5'-GTGGTCTGATCAACGGTAA-3'
3'-CACCAGACTAGTTGCCATT-5'
the number of repeats of each individual's tandem repeats regions can be different creating a specific DNA profile. when using one primer pair in different individuals, which phrase describes the PCR product?
different length may be found in each individual
what happens to the probability of a 100% match between two different individuals when using 13 sets of primers for the DNA profile instead of one?
it decreases
how many copies of DNA are required to see bands on the electrophoresis gel?
millions of copies
which word describes the charge of the DNA?
negatively charged
DNA is negatively charged. to which location in the electrophoresis gel does it migrate?
the positive pole
who is the murderer?
the rival scientist
what are the building blocks of new copies of DNA?
nucleotides
what is the function of primers in a PCR?
they bind specific sites on the template DNA to initiate and direct DNA synthesis
what would happen if no polymerase was added to the PCR?
new DNA would not be generated
which reagent acts as a template for the DNA polymerase so that it knows which new DNA to make?
DNA from a blood sample
DNA polymerase binds to the template DNA. in which direction is the new DNA subsequently synthesized?
5' to 3'
why is the Taq-polymerase special compared to most other polymerases?
it can resist high temperatures
what can contamination of reagents lead to?
unreliable results
how many sets of primers are needed for DNA profiling?
13
what is the purpose of PCR?
to copy and then make many copies of a specific region of DNA
why is a PCR cycle repeated 30 times?
to get enough DNA
what can a DNA ladder help determine?
the length of a fragment
why is it possible to distinguish individuals by running these PCR products on a gel?
the PCR products are different lengths [Show Less]