DNA Profiling Lab Flashcards
Learn more about DNA in the context of Forensic Science Lab
Three reasons for DNA extraction
Genetic testing, body identification, Analysis of forensic evidence
Inside each nucleus is how much DNA?
2 meters
What cells are used to extract DNA?
Cheek cells
4 steps needed to purify DNA
Collect cheek cells, burst cells open to release DNA, separate DNA from proteins and debris, isolate concentrated DNA
‘Lysis’ is a greek word that means to
separate
Lysis solution contains what two ingredients
Salts & Detergents
When salt is added what happens?
Proteins and debris clump together
What allows us to see DNA with the naked eye?
Isopropyl alcohol
DNA is stored in the
freezer
When salty DNA comes in contact with alcohol it becomes
undissolved
When salty DNA becomes undissolved due to coming in contact with alcohol it’s called
precipitation
PCR stands for
Polymerase Chain Reaction
PCR is used for everyday things like
Genetic engineering, body identification and medical testing
The human genome is made up of
3 billion chemical base pairs
What is special about the DNA polymerase used in PCR
Enzymes that copy DNA
Machine used to heat and cool tube
Thermal cycler
At what temperature does the double helix seperate?
95C
At what cycle does the desired part of the amplified DNA show up
Cycle 3
Primers in PCR
Short single stranded DNA sequences used in PCR to amplify specific DNA regions for analysis.
Enzyme that allows function at high temperatures
Thermus Aquaticus
Gel electrophoresis allows for sorting of DNA strands according to
Size
What is used to filter in Gel electrophoresis?
Gel
What makes the DNA move in Gel electrophoresis?
Electricity
What must be done to see DNA groups in Gel electrophoresis?
Fluorescent dye and UV light
Agarose is made of
natural polymer of red algae
Buffer is helpful for
maintaining a constant pH to avoid damage of DNA or proteins
Two reasons for adding loading buffer to DNA sample
Increases sample density & visible tracking dyes
Why should you load a standard in Gel electrophoresis?
Accurately determine size of DNA fragments
DNA has a ________ charge
negative
What chemical is used to stain DNA?
Ethidium bromide
Ethidium bromide is dangerous because it can cause
genetic damage
Essential lengths of 3 bands
100bp, 300bp, and 500bp
DNA fingerprints also go by
DNA profiling & DNA testing
__% of DNA is the same in everyone
99.9
What temperature does the DNA go through for PCR
95C-> 50C–>72C