Download Laboratory #1 Lecture Guide: Forensic DNA Fingerprinting

Laboratory #1 Lecture Guide: Forensic DNA Fingerprinting
Advanced DNA/Genetics
Kelavkar
Wheeler High School Center for Advanced Studies
Day #1: Restriction Enzyme Digest
1. Why does a DNA molecule have an overall negative charge?
2. What’s the function of a restriction enzyme?
3. Why might it be evolutionary advantageous for bacteria to evolve to produce restriction
enzymes?
4. What’s another way to say ‘restriction enzyme’ (really, this is the more scientific way)?
5. How are restriction enzymes named?
6. As you know by now, restriction enzymes are ‘molecular scissors’ that cut up pieces of
DNA. What are the two possible end products for the cutting of RE’s? Draw two
pictures below.
7. What’s a palindromic sequence?
8. What’s RFLP and why is it so important when conducting gel electrophoresis?
Day #2: Agarose Gel Electrophoresis
1. What is the whole point of gel electrophoresis?
2. Why must we always load the DNA on the negative end of the chamber?
3. What is the relationship between the gel’s density and the movement of the DNA
fragments?
4. Why must we stain our gel’s?
Day #3: Visualization of Gel
1. Use the graph below to explain how you plan on going about graphing your data.
100,000
Distance (mm)
23,000
11.0
9,400
13.0
6,500
15.0
4,400
18.0
2,300
23.0
2,000
24.0
10,000
Size, base pairs
Size (bp)
B
1,000
100
0
5
10
15
Distance, mm
20
A
25
30