Reverse transcriptase can synthesise

Options

A. (a) DNA → DNA
B. (b) DNA → RNA
C. (c) RNA → Protein
D. (d) RNA → DNA

Answer

**Step-by-Step Solution:**

1. **Understanding Reverse Transcriptase**: Reverse transcriptase is an enzyme that synthesizes DNA from an RNA template. This is a key function of the enzyme, which is primarily found in retroviruses.

2. **Central Dogma of Molecular Biology**: The central dogma states that genetic information flows from DNA to RNA to protein. Typically, DNA is transcribed into RNA, and RNA is translated into proteins.

3. **Identifying the Exception**: Reverse transcriptase operates in the opposite direction of the central dogma. Instead of synthesizing RNA from DNA, it synthesizes DNA from RNA. This process is known as reverse transcription.

4. **Analyzing the Options**:
- **Option A (DNA to DNA)**: This describes replication, not the function of reverse transcriptase.
- **Option B (DNA to RNA)**: This describes transcription, which is not the function of reverse transcriptase.
- **Option C (RNA to protein)**: This describes translation, which is also not the function of reverse transcriptase.
- **Option D (RNA to DNA)**: This accurately describes the function of reverse transcriptase, which synthesizes DNA from an RNA template.

5. **Conclusion**: Based on the analysis of the options, the correct answer is **D (RNA to DNA)**, as this is the process facilitated by reverse transcriptase.

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