Question

Choose the statement which is not true about get electrophoresis:

• A. DNA fragments are forced to move towards the anode under an electric field
• B. Exposure to UV radiation is required
• C. DNA fragments can be visualized by adding agarose
• D. DNA fragments separate according to their size

Answer 1

Answer:

C. DNA fragments can be visualized by adding agarose

• Gel electrophoresis is a laboratory method used to separate mixtures of DNA, RNA, or proteins according to molecular size.

• In gel electrophoresis, the molecules to be separated are pushed by an electrical field through a gel that contains small pores.

• DNA, being negatively charged, will move from the cathode (−) to the anode (+) when voltage is applied.

• Once electrophoresis is complete, the gel is stained with an intercalating dye such as ethidium bromide. Ethidium bromide binds to the bases of DNA and fluorescence under UV light to allow for viewing.

• The relative size of the fragments produced on the gel is determined by comparing their position to that of a molecular weight marker.