Electrophoresis (CP 14)

Question 1

State the name of the technique for separating DNA fragments

Answer 1

Electrophoresis

Question 2

Describe how to carry out this technique

Answer 2

Put DNA fragments into not a prepared electrophoresis apparatus. Should contain a buffer and agarose with prepared wells for DNA fragments. Turn on apparatus and let electrodes separate fragments

Question 3

Explain why the DNA moves to the positive electrode during gel electrophoresis

Answer 3

As the phosphate backbone of DNA is negatively charged it will move to the positive electrode

Question 4

Explain how the size of DNA fragments determines how far they move in the gel.

Answer 4

DNA fragments will move through a mesh within the gel so movement is dependent on size. The larger the fragments the less they’ll move but the smaller means the further as they can fit through the mesh