NEETZoologyBiotechnology - Principles and Processes
Criterion for DNA fragments movement on agarose gel during gel electrophoresis is
Options
- AThe larger the fragment size, the farther it moves
- BThe smaller the fragment size, the farther it moves
- CPositively charged fragments move to farther end
- DNegatively charged fragments do not move
Correct answer
B. The smaller the fragment size, the farther it moves
Step-by-step solution
Since DNA fragments are negatively charged molecules they can be separated by forcing them to move towards the anode under an electric field through a medium/matrix. Nowadays the most commonly used matrix is agarose which is a natural polymer extracted from sea weeds. The DNA fragments separate (resolve) according to their size through sieving effect provided by the agarose gel. Hence, the smaller the fragment size the farther it moves.The separated DNA fragments can be visualised only after staining the DNA with a