NEETZoologyBiotechnology - Principles and Processes
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In agarose gel electrophoresis, the smallest DNA fragment travels the maximum distance from the well. Reason (R): Agarose gel provides a sieving effect, and the negatively charged DNA fragments are pulled towards the anode under an electric field. In the light of the above statements, choose the mo
Options
- ABoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
- BBoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
- CAssertion (A) is true but Reason (R) is false.
- DAssertion (A) is false but Reason (R) is true.
Correct answer
B. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
Step-by-step solution
Assertion (A) is true. During gel electrophoresis, the DNA fragments separate according to their size through the sieving effect provided by the agarose gel. Therefore, the smaller the fragment size, the farther it moves from the well. Reason (R) is true and correctly explains the Assertion. DNA fragments are negatively charged molecules, so they are forced to move towards the anode under an electric field through the agarose matrix. The matrix acts as a sieve, allowing smaller fragments to move faster and farther