GRE Subject Test: Chemistry : Electrochemical Analyses

Study concepts, example questions & explanations for GRE Subject Test: Chemistry

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Example Questions

Example Question #1 : Electrochemical Analyses

Once a sample of DNA is isolated, it is loaded on an agarose electrophoresis gel, as shown below. Once the sample has run, where will the student find the DNA?



Possible Answers:

Red section

Green section

It is impossible to tell without knowing the size of the DNA fragments

It is impossible to tell without knowing the charge of the DNA

Correct answer:

Green section


DNA is negatively charged, so it will migrate toward the positive electrode during electrophoresis. As a result, it will migrate from the center line into the green region of the gel.

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