Which of the following bases is`//`are derivative of purines ?

Options

A. Uracil
B. Cytosine
C. Adenine
D. Thymine

Answer

To determine which of the following bases are derivatives of purines, we first need to understand what purines are and identify the bases that fall under this category.

### Step-by-Step Solution:

1. **Define Purines**: Purines are a type of nitrogenous base that have a double-ring structure composed of carbon and nitrogen atoms. The two main purines found in nucleic acids are adenine (A) and guanine (G).

2. **List Common Nitrogenous Bases**: The common nitrogenous bases can be categorized into two groups: purines and pyrimidines.
- **Purines**: Adenine (A) and Guanine (G)
- **Pyrimidines**: Cytosine (C), Thymine (T), and Uracil (U)

3. **Identify the Derivatives of Purines**: The derivatives of purines are compounds that are structurally related to adenine and guanine. This includes:
- Adenine
- Guanine

4. **Conclusion**: Based on the definitions and classifications, the bases that are derivatives of purines are adenine and guanine.

### Final Answer:
The bases that are derivatives of purines are adenine and guanine.

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