A fragment of DNA, cut by a restriction enzyme, forms bonds with other DNA molecules that have

Options

A. been fragmented by the same restriction enzyme
B. sticky ends
C. plasmid components
D. attached

Answer

To solve the question, we need to understand how DNA fragments interact with each other after being cut by restriction enzymes. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Understanding Restriction Enzymes**:
- Restriction enzymes are proteins that cut DNA at specific sequences. They can create two types of ends: sticky ends and blunt ends.
- Sticky ends are created when the enzyme cuts in a staggered manner, leaving overhanging sequences that can easily bond with complementary sticky ends of other DNA fragments.
- Blunt ends are formed when the enzyme cuts straight across both strands of the DNA, leaving no overhang.

2. **Analyzing the Options**:
- **Option A**: "Have been fragmented by the same restriction enzyme" - This option suggests that the DNA fragments can bond if they were cut by the same enzyme, which would create compatible ends (either sticky or blunt).
- **Option B**: "Sticky ends" - While sticky ends can bond with other sticky ends, this option is too specific and does not encompass all possibilities.
- **Option C**: "Plasmid component" - This option does not directly relate to the bonding of DNA fragments cut by restriction enzymes.
- **Option D**: "Attached" - This option is vague and does not provide a clear answer.

3. **Choosing the Correct Answer**:
- The most accurate answer is **Option A**: "Have been fragmented by the same restriction enzyme". This is because DNA fragments cut by the same restriction enzyme will have compatible ends, allowing them to bond together.

4. **Conclusion**:
- Therefore, the correct answer to the question is that a fragment of DNA cut by a restriction enzyme forms bonds with other DNA molecules that have been fragmented by the same restriction enzyme.