Question

What is the criterion for DNA fragment's movement on agarose gel during gel electrophoresis?

• A. The larger the fragment size, the farther it moves
• B. The smaller the fragment size, the farther it moves
• C. Positively charged fragments move farther end
• D. Negatively charged fragments do not move

Answer 1

The correct option is B

The smaller the fragment size, the farther it moves

The correct option is B

Explanation of the correct option:

1. The sieving effect causes DNA fragments to move across an agarose gel according to their size during gel electrophoresis.
2. The smallest fragments travel the most distance.
3. DNA is a negatively charged molecule and it will migrate to the positively charged electrode when an electric current is supplied to the gel.
4. The shorter strands of DNA move faster across the gel than longer strands, the fragments are organized in size order.

Final answer: The smaller the fragment size, the farther it moves is the criterion for DNA fragments movement on agarose gel during gel electrophoresis.