The enzyme used to remove the phosphate group from the 5’ end of DNA molecule is :

Options

A. phosphorylase
B. DNA polymerase
C. DNA ligase
D. alkaline phosphatase

Answer

To solve the question regarding the enzyme that removes the phosphate group from the 5’ end of a DNA molecule, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding DNA Structure**:
- DNA molecules have two ends: the 3’ end, which has a hydroxyl (-OH) group, and the 5’ end, which has a phosphate group attached. This structural knowledge is crucial for identifying the correct enzyme.

2. **Analyzing the Options**:
- **Option 1: Phosphorylase**: This enzyme is involved in adding phosphate groups to molecules, not removing them. Therefore, it cannot be the correct answer.
- **Option 2: DNA Polymerase**: This enzyme is primarily involved in DNA replication, where it adds nucleotides to a growing DNA strand. It does not function to remove phosphate groups, making it an incorrect choice.
- **Option 3: DNA Ligase**: This enzyme is responsible for joining DNA fragments together, particularly during DNA replication and repair. It does not remove phosphate groups, so it is not the right answer.
- **Option 4: Alkaline Phosphatase**: This enzyme specifically removes phosphate groups from various molecules, including the 5’ end of DNA. This makes it the correct choice for the question.

3. **Conclusion**:
- After analyzing all the options, the enzyme that removes the phosphate group from the 5’ end of a DNA molecule is **Alkaline Phosphatase**.

### Final Answer:
The enzyme used to remove the phosphate group from the 5’ end of the DNA molecule is **Alkaline Phosphatase**.

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