The main difference between DNA and RNA is _______

Options

A. In the nature of sugar alone
B. in the nature of purines alone
C. In the nature of sugar and pyrimidines
D. none of these

Answer

To determine the main difference between DNA and RNA, we can break down the components of each molecule and identify their distinct features step by step.

### Step-by-Step Solution:

1. **Identify the Components of DNA and RNA**:
- Both DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are nucleic acids composed of three main components: a sugar, a phosphate group, and nitrogenous bases.

2. **Examine the Sugar Component**:
- DNA contains deoxyribose sugar, which lacks one oxygen atom compared to ribose sugar.
- RNA contains ribose sugar, which has one more oxygen atom than deoxyribose.

3. **Analyze the Nitrogenous Bases**:
- DNA has four nitrogenous bases: adenine (A), thymine (T), cytosine (C), and guanine (G).
- RNA also has four nitrogenous bases: adenine (A), uracil (U), cytosine (C), and guanine (G).
- The key difference here is that RNA contains uracil instead of thymine, which is present in DNA.

4. **Summarize the Differences**:
- The main differences between DNA and RNA can thus be summarized as:
- The type of sugar: DNA has deoxyribose, while RNA has ribose.
- The type of nitrogenous base: DNA has thymine, while RNA has uracil.

5. **Choose the Correct Option**:
- Based on the differences identified, the correct answer to the question "The main difference between DNA and RNA is _______" is "in the nature of sugar and primidines."

### Final Answer:
The main difference between DNA and RNA is in the nature of sugar and primidines.

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