In DNA and RNA, pentose sugar has furanose ring. It is

Options

A. aldose type
B. ketose type
C. pyranose
D. nonreducing type

Answer

To answer the question regarding the pentose sugar in DNA and RNA having a furanose ring, we can break down the solution step by step:

### Step-by-Step Solution:

1. **Identify the Structure of Pentose Sugar**:
- Both DNA (Deoxyribonucleic Acid) and RNA (Ribonucleic Acid) contain a pentose sugar. The pentose sugar in DNA is deoxyribose, while in RNA it is ribose.

2. **Understand the Ring Structure**:
- The pentose sugar forms a five-membered ring structure known as a furanose ring. This ring consists of four carbon atoms and one oxygen atom.

3. **Determine the Type of Sugar**:
- The furanose ring can be classified based on the type of carbonyl group present in the sugar.
- If the carbonyl group is at the end of the carbon chain (aldehyde), the sugar is classified as an aldose. If the carbonyl group is within the carbon chain (ketone), it is classified as a ketose.

4. **Classify the Pentose Sugar**:
- Since the pentose sugars in both DNA and RNA (deoxyribose and ribose) have an aldehyde group when in their linear form, they are classified as aldoses.

5. **Select the Correct Option**:
- Among the given options (aldose type, ketose type, pyranose type, and non-reducing type), the correct classification for the pentose sugar in DNA and RNA is **aldose type**.

### Final Answer:
The pentose sugar in DNA and RNA has a furanose ring and is of **aldose type**.

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