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Consider the give statements w.r.t gel e...

Consider the give statements w.r.t gel electrophoresis
I. Dna can be separated by forcing them to move towards cathode under an electric field.
II. DNA fragments separated according to their size throug sieving effect provided by agarose gel.
III. The used matrix in this technique is agarose which is an artificial polymer
Which of the following statements is/are correct?

A

I andII

B

II only

C

II and III

D

I,II and III

Text Solution

AI Generated Solution

The correct Answer is:
**Step-by-Step Solution:** 1. **Analyze Statement I**: The first statement claims that DNA can be separated by forcing them to move towards the cathode under an electric field. In gel electrophoresis, DNA is negatively charged due to its phosphate backbone. When an electric field is applied, DNA moves towards the anode (positive electrode), not the cathode (negative electrode). Therefore, this statement is **incorrect**. 2. **Analyze Statement II**: The second statement states that DNA fragments are separated according to their size through the sieving effect provided by agarose gel. This is true; agarose gel acts as a molecular sieve, allowing smaller DNA fragments to move faster through the gel matrix while larger fragments move more slowly. Thus, this statement is **correct**. 3. **Analyze Statement III**: The third statement claims that the matrix used in this technique is agarose, which is an artificial polymer. Agarose is actually derived from agar, which is obtained from algae, making it a natural polymer rather than an artificial one. Therefore, this statement is **incorrect**. 4. **Conclusion**: Based on the analysis of the statements: - Statement I: Incorrect - Statement II: Correct - Statement III: Incorrect The only correct statement is the second one. 5. **Final Answer**: The correct option is **2nd only**. ---
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