The purine bases present in nucleic acids are .......... and ..............

Explanation

To answer the question regarding the purine bases present in nucleic acids, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Nucleic Acids**: Understand that nucleic acids are primarily DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). These are essential biomolecules in living organisms.

2. **Understand the Composition**: Recognize that nucleic acids consist of three main components: a sugar (ribose in RNA and deoxyribose in DNA), a phosphate group, and nitrogenous bases.

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