cell bio homework 3 Essay

950 WordsDec 3, 20134 Pages
Cellular Biology Lab – Homework #3 Due the week of Nov. 4th You may use the lab manual, pre-lab lectures, and credible internet resources, however you may not use your cell bio lab classmates as a resource. You will most likely see this material again on the Final and I highly encourage you to work individually and seek help from myself or your TA. Plagiarism will result in an automatic zero. 1. In the cell bio lab, we use company manufactured gels, however you can make you own polyacrylamide gels. List all of the ingredients found in an SDS-PAGE gel. Which ingredients are responsible for polymerizing the solution? How does the percentage of acrylamide effect the migration of proteins (ex: 4% gel vs. 18% gel)? The percent…show more content…
In this gel above, which lanes contain the positive and negative controls? Describe the information you can deduce by comparing and contrasting the negative control and lane 2 protein bands. Lane 3 is the positive control and lane 4 is the negative control. By comparing lane 4 the negative control and lane 2 the purified protein X it is noticeable that the second band in lane 2 is the elution buffer due to the fact that the negative control only contains elution buffer and only forms one band which matches up with the second band in lane 2. c. Describe the information you can deduce by comparing and contrasting the positive control lane and lane 2 protein bands. By comparing lane 3 the positive control to lane 2 the purified protein X it is noticeable that the first band is the unknown protein X due to the fact that the positive control only contains purified protein X and only forms one band which matches up with the first band in lane 2. d. You don’t know the molecular weight (MW) of protein X and you are not able to find that information in the scientific literature. The best way to determine the MW of a protein using an SDS-PAGE gel is to use the protein ladder bands to create a Log(MW) vs. Rf graph and calculate the MW from the line of best fit. What is the equation to calculate the Rf of a protein band? Make a table of the Log(MW) and the Rf values for all 5 protein ladder bands. Describe any trends you see in the table
Open Document