Which of the following is correct regarding the separation of DNA fragments during gel electrophoresis?

Options

A. Smallest fragment will move to the farthest point towards cathode.
B. Smallest fragment will move to the farthest point towards anode.
C. Largest fragment will move to the farthest point towards anode.
D. Largest fragment will move to the farthest point towards cathode.

Answer

To solve the question regarding the separation of DNA fragments during gel electrophoresis, we need to understand the principles of this technique. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Basics of Gel Electrophoresis
Gel electrophoresis is a method used to separate DNA fragments based on their size (molecular weight) and charge. DNA fragments are negatively charged due to the phosphate backbone.

**Hint:** Remember that DNA is negatively charged and will move towards the positive electrode (anode).

### Step 2: Identify the Movement of DNA Fragments
When an electric current is applied, DNA fragments migrate through the gel towards the anode. Smaller fragments can navigate through the gel matrix more easily than larger fragments.

**Hint:** Smaller fragments move faster than larger fragments in the gel.

### Step 3: Analyze the Options
Now, let's evaluate the provided options:

1. **Smallest fragment will move to the farthest point towards cathode.**
- This is incorrect. Small fragments move towards the anode, not the cathode.

2. **Smallest fragment will move to the farthest point towards anode.**
- This is correct. Small fragments move faster and travel farther towards the anode.

3. **Largest fragment will move to the farthest point towards anode.**
- This is incorrect. Larger fragments move slower and do not reach the anode as quickly.

4. **Largest fragment will move to the farthest point towards cathode.**
- This is also incorrect. Larger fragments will not move towards the cathode; they will lag behind and not reach the anode.

### Step 4: Conclusion
Based on the analysis, the correct statement regarding the separation of DNA fragments during gel electrophoresis is that the smallest fragment will move to the farthest point towards the anode.

**Final Answer:** The correct option is: **Smallest fragment will move to the farthest point towards anode.**