Question

In the nuclease digestion experiment, the scientists use a technique called gel electrophoresis. While this is related to SDS-PAGE used in the separation of membrane proteins, it is NOT THE SAME thing. From the list below, choose all the ways that gel electrophoresis is done for nuclease digestion is different from the gel electrophoresis in SDS-PAGE.

Group of answer choices

1.Used to separate DNA or RNA.

2.Used to separate proteins.

3.Prteins and DNA must be separated prior to running the gel (in addition to any digestion treatments).

4.Only the pretein is loaded into the gel.

5.Sample needs to be pre-treated with SDS, so that it has a uniform negative charge.

6.Gel is made of agarose.

7.Gel is made of polyacrylamide.

8.SDS is not required, as sample already carries a uniform negative charge.

9.Proteins and DNA must be separated prior to running the gel (in addition to any digestion treatments).

10.Only the DNA is loaded into the gel.

Answer 1

sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS PAGE is a protein separation method where proteins are separated based on their molecular masses. SDS is a detergent which denatures proteins and therefore, proteins take linear appearance. Also, SDS provides a uniform negative charge to the sample proteins. Polyacrylamide is used as it is easy to handle and pore size can be controlled easily. It works like a mesh containing many holes through which proteins run from negative to the positive side of the apparatus.

But in agarose gel electrophoresis, as DNA is already negative, no SDS treatment is needed.

In both cases, protein and DNA need to be separated before running the gel.

​​​​​​The answer choices grouped for SDS PAGE and agarose gel electrophoresis is given below.

SDS PAGE-------

2.Used to separate proteins.

3. Proteins and DNA must be separated prior to running the gel.

4. Only the protein is loaded into the gel.

5. Sample needs to be pre-treated with SDS.

7. Gel is made of polyacrylamide.

AGAROSE GEL ELECTROPHORESIS-----------

1. Used to separate DNA or RNA.

6. Gel is made of agarose.

8. SDS is not required, as sample already have uniform negative charge ( as DNA or RNA is negatively charged molecules).

9. Protein and DNA must be separated prior to running the gel.

10. Only DNA is loaded into the gel.