What is the criterion for DNA fragments movement on agarose gel during gel electrophoresis?
Answer: (B) The smaller the fragment size, the farther it moves. Answer: (B) The smaller the fragment size, the farther it moves Solution: In gel electrophoresis, negatively charged DNA fragments move towards the anode through an agarose matrix and separate according to size by the sieving effect of the gel.
- 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 to farther end
- D.Negatively charged fragments do not move
Correct Answer
(B) The smaller the fragment size, the farther it moves
Solution & Explanation
Answer: (B) The smaller the fragment size, the farther it moves Solution: In gel electrophoresis, negatively charged DNA fragments move towards the anode through an agarose matrix and separate according to size by the sieving effect of the gel. Smaller fragments meet less resistance and therefore migrate farther than larger fragments. NCERT Reference: Ch 9, p.168, line(s) 14 — "by the agarose gel. Hence, the smaller the fragment size, the farther it"