Purine nucleosides have

Options

A. 5-3 phosphodiester bond
B. 1-9 glycosidic linkage
C. 1-1' glycosidic linkage
D. H-bonds

Answer

To solve the question regarding purine nucleosides, we need to understand the structure of nucleosides and the types of linkages involved.

### Step-by-Step Solution:

1. **Understand Nucleosides**:
- Nucleosides are composed of two main components: a nitrogenous base and a sugar molecule (either ribose in RNA or deoxyribose in DNA). They do not contain phosphate groups.

2. **Identify the Types of Nitrogenous Bases**:
- There are two categories of nitrogenous bases: purines and pyrimidines.
- Purines include adenine and guanine, which have a nine-membered ring structure.
- Pyrimidines include cytosine, thymine, and uracil, which have a six-membered ring structure.

3. **Analyze the Options**:
- **Option A**: "5 prime to 3 prime phosphodiester bond" - This is incorrect because nucleosides do not have phosphate groups; phosphodiester bonds are found in nucleotides.
- **Option B**: "1 prime to 9 prime glycosidic linkage" - This is correct for purine nucleosides. The nitrogenous base (purine) forms a glycosidic bond with the sugar at the 1' carbon of the sugar and the 9th nitrogen of the purine.
- **Option C**: "1 to 1 prime glycosidic linkage hydrogen bond" - This is incorrect for purines. While pyrimidines have a 1' to 1' linkage, purines specifically have a 1' to 9' linkage.

4. **Conclusion**:
- The correct answer is **Option B**, which states that purine nucleosides have a "1 prime to 9 prime glycosidic linkage."