Question

Study the given figure carefully and select the correct statements regarding this.

I. It represents typical agarose gel electrophoresis showing differential migration of DNA fragments.
II. Lane $1$ contains undigested DNA fragments.
III. Lanes $2$ to $4$ contain digested DNA fragment.
IV. Smallest DNA bands are present at $A$ position and largest DNA bands are present at $B$ position.

• A. I, II and III
• B. I, II and IV
• C. II and III
• D. III and IV

Answer 1

Answer: (A)

Largest DNA bands will be at (A) and the smallest DNA bands will be at (B) because in this technique, DNA moves according to their size through sieving effect provided by the agarose gel. Hence, the smaller the fragment size, the farther it moves.