Reverse transcriptase

Options

A. Disintegrates host DNA
B. Polymerises host DNA
C. Translates host DNA
D. Transcribes viral RNA to cDNA

Answer

**Step-by-Step Solution:**

1. **Understanding Reverse Transcriptase**: Reverse transcriptase is an enzyme that synthesizes complementary DNA (cDNA) from an RNA template. This is a key process in retroviruses, where the viral RNA is converted into DNA.

2. **Analyzing the Options**:
- **Option 1: Disintegrates host DNA**: This option suggests that reverse transcriptase cuts host DNA into fragments. However, this is not the function of reverse transcriptase. Instead, this function is typically associated with endonucleases. Therefore, this option is incorrect.

- **Option 2: Polymerizes host DNA**: This option implies that reverse transcriptase is responsible for synthesizing or replicating host DNA. However, reverse transcriptase does not polymerize host DNA; it synthesizes cDNA from RNA. Host DNA replication is carried out by DNA polymerase. Thus, this option is also incorrect.

- **Option 3: Translates host DNA**: This option indicates that reverse transcriptase translates host DNA into proteins. However, translation is the process of synthesizing proteins from mRNA, which is done by ribosomes and not by reverse transcriptase. Therefore, this option is incorrect as well.

- **Option 4: Transcribes viral RNA to cDNA**: This option correctly describes the function of reverse transcriptase. It synthesizes cDNA from viral RNA, which is a crucial step in the life cycle of retroviruses. Hence, this option is correct.

3. **Conclusion**: After evaluating all the options, the correct function of reverse transcriptase is to transcribe viral RNA to cDNA, making **Option 4** the correct answer.

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