The nuclease enzyme which brings its attack from the free and of a Polynucleotide, is called

Options

A. Exonuclease
B. Kinase
C. Polymerase
D. Endonuclease

Answer

To solve the question, "The nuclease enzyme which brings its attack from the free end of a Polynucleotide, is called," we can follow these steps:

### Step 1: Understand the Types of Nucleases
Nucleases are enzymes that cut the bonds between nucleotides in nucleic acids (DNA and RNA). There are two main types of nucleases:
- **Exonucleases**: These enzymes remove nucleotides from the ends of a polynucleotide chain.
- **Endonucleases**: These enzymes cut nucleotides within the polynucleotide chain.

### Step 2: Analyze the Question
The question specifically asks for a nuclease that attacks from the free end of a polynucleotide. This indicates that we are looking for an enzyme that works at the terminal ends of the nucleotide chain.

### Step 3: Evaluate the Options
- **Exonuclease**: As mentioned, this enzyme removes nucleotides from the ends of the chain.
- **Endonuclease**: This enzyme cuts within the chain, not at the ends.
- **Kinase**: This enzyme is involved in the phosphorylation process, not in cutting nucleotides.
- **Polymerase**: This enzyme synthesizes DNA or RNA by adding nucleotides, not cutting them.

### Step 4: Identify the Correct Answer
Since we are looking for the enzyme that acts on the free ends of the polynucleotide chain, the correct answer is **Exonuclease**.

### Final Answer
The nuclease enzyme which brings its attack from the free end of a polynucleotide is called **Exonuclease**.

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