E dna by itself is not visible to the naked eye when

(e.) DNA by itself is not visible to the naked eye when it is in solution. How can one visualize
DNA fragments in a gel? To visualize DNA in this exercise, what precautions must be taken?
(2) GROUP: Analyze your gel. Show your work.
(a.) Include a picture of your gel, labeling all components (samples names, DNA bands, ladder,
etc.) What is the purpose of
- the positive control DNA sample?

Sydney Horton
Sjh2643
Group Members: Shruthi, Taylor, Maha Exercise: 4 Date: 2/11 LI: Sanjeev Unique: 49150 Day: T Room: PAI 1.08
Lab Start Time: 6 PM
Exercise 4 Page
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(b.) Prepare a standard curve showing the relationship between known size (in bp) of the molecular
weight marker/ fragments (bands of the MW ladder) and the migration distance for each of the
bands. Use data from the group’s agarose gel to graph a scatter plot in MS Excel. Place the
logarithm of each of the DNA marker sizes (in bp ) along the Y-axis of the graph and the
migration distances on the X-axis. Perform a linear regression analysis and include the line
equation and regression coefficient (R
2
).
(c.) Using the linear regression equation, estimate the approximate size of each of the DNA band(s)
found in each of the samples.

Sydney Horton
Sjh2643
Group Members: Shruthi, Taylor, Maha Exercise: 4 Date: 2/11 LI: Sanjeev Unique: 49150 Day: T Room: PAI 1.08
Lab Start Time: 6 PM
Page
4
of
9
(d.) Interpret your results. Compare the size of the bands in the “cut” (+) and “uncut” (–) lanes. Did
you see any evidence of supercoiled plasmids or nicked/relaxed plasmids? Were your
restriction digestion reactions successful? What is the total size of the pLAF plasmid? How
many base pairs (bp) are between the EcoRI and BpmI restriction sites? Be sure to use the data
from your gel to explain your answer.