The stickiness of DNA ends faciliates the action of which enzyme

Options

A. DNA polymerases
B. DNA ligase
C. Restriction endonculeases
D. Alkaline phosphatase

Answer

**Step-by-Step Solution:**

1. **Understanding Sticky Ends**: Sticky ends of DNA are formed when restriction endonucleases cut the DNA at specific sequences, resulting in overhanging ends. These overhangs can easily pair with complementary sequences of DNA.

2. **Identify the Role of Enzymes**:
- **DNA Polymerase**: This enzyme is involved in DNA replication and synthesizes new DNA strands by adding nucleotides. It does not specifically utilize sticky ends for its action.
- **DNA Ligase**: This enzyme is responsible for joining two DNA fragments together by forming phosphodiester bonds. The presence of sticky ends facilitates this process because the overhangs can easily anneal to each other, making it easier for DNA ligase to join them.
- **Restriction Endonucleases**: These enzymes cut DNA to create sticky or blunt ends. They do not utilize sticky ends; rather, they create them.
- **Alkaline Phosphatase**: This enzyme removes phosphate groups from nucleotides and is not directly involved in the joining of DNA fragments.

3. **Conclusion**: The stickiness of DNA ends facilitates the action of DNA ligase, as it helps in the joining of DNA fragments by making it easier for the enzyme to form bonds between the sticky ends.

4. **Final Answer**: The correct answer is **DNA ligase**.

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