Question

Select the correct statements for D gel electrophoresis:
A. Small D fragments remain near to the well
B. Longer D fragments move towards the negative end of the gel
C. Longer D fragments remain near to the well
D. Smaller D fragments move towards the positive end of the gel

• A. A and D Only
• B. B and C Only
• C. A and B Only
• D. C and D Only

Hint:

D Gel Electrophoresis Principles:
1. D is negative $\to$ Moves toward Positive Anode ($+$).
2. Small fragments = Move faster, migrate farther down gel.
3. Large/Long fragments = Move slower, stay near the top wells.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
The question asks to identify the true statements describing D migration dymics during agarose gel electrophoresis.

Step 2: Key Formula or Approach:
D possesses a uniform negative charge-to-mass ratio due to its phosphate backbone ($\text{PO}_4^{3-}$). When subjected to an electric field, D migrates toward the positive anode ($+$). The gel matrix acts as a sieve: smaller fragments experience less frictiol resistance and travel faster/farther, whereas larger fragments are retarded and remain close to the loading wells.

Step 3: Detailed Explation:

• Alysis of Statement A: "Small D fragments remain near to the well" $\to$ False. Small fragments migrate quickly through pores toward the bottom (anode) of the gel.

• Alysis of Statement B: "Longer D fragments move towards the negative end of the gel" $\to$ False. All D fragments move away from the negative cathode towards the positive anode.

• Alysis of Statement C: "Longer D fragments remain near to the well" $\to$ True. High molecular weight (longer) D fragments migrate slowly due to gel sieving and stay near the loading wells at the top.

• Alysis of Statement D: "Smaller D fragments move towards the positive end of the gel" $\to$ True. Smaller fragments migrate rapidly toward the positive electrode ($+$).

Step 4: Fil Answer:
Statements C and D are correct.