In structure of D.N.A and R.N.a nucleotides are joined together by phosphodiester linkage between

Options

A. `5'` and `2'` carbon atoms of the pentose sugar
B. `5'` and `3'` carbon atoms of the petose suggar
C. `5'` and `1'` carbon atoms of pentose sugar
D. `3'` and `1'` carbon atoms of pentose sugar

Explanation

To solve the question regarding the structure of DNA and RNA and how nucleotides are joined together by phosphodiester linkage, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Nucleotides**:
- A nucleotide is the basic building block of DNA and RNA. Each nucleotide consists of three components: a phosphate group, a sugar molecule (deoxyribose in DNA and ribose in RNA), and a nitrogenous base.

**Hint**: Remember that nucleotides are the fundamental units that make up nucleic acids.

2. **Phosphodiester Linkage**:
- Nucleotides are connected to each other through phosphodiester bonds. This bond forms between the phosphate group of one nucleotide and the hydroxyl group on the sugar of another nucleotide.

**Hint**: Focus on how the phosphate group interacts with the sugar to form a bond.

3. **Numbering the Carbon Atoms**:
- In the sugar molecule of the nucleotide, the carbon atoms are numbered starting from the carbon atom that is attached to the nitrogenous base. The numbering goes as follows:
- The first carbon (1') is attached to the base,
- The second carbon (2') is attached to the hydroxyl group (in RNA) or hydrogen (in DNA),
- The third carbon (3') has a hydroxyl group that participates in the phosphodiester bond,
- The fourth carbon (4') is part of the sugar ring,
- The fifth carbon (5') is attached to the phosphate group.

**Hint**: Visualize the sugar structure and remember the order of carbon numbering.

4. **Formation of the Phosphodiester Bond**:
- The phosphodiester bond specifically forms between the 3' carbon of one sugar and the 5' carbon of the adjacent sugar. This creates a backbone for the nucleic acid strand.

**Hint**: Pay attention to the directionality of the strand; the 3' end connects to the 5' end of the next nucleotide.

5. **Conclusion**:
- Therefore, in the structure of DNA and RNA, nucleotides are joined together by phosphodiester linkages between the 3' carbon of one nucleotide and the 5' carbon of the next nucleotide.

**Hint**: Conclude by summarizing the key points about the linkage.

### Final Answer:
The correct answer is that nucleotides in DNA and RNA are joined together by phosphodiester linkages between the 3' carbon of one nucleotide and the 5' carbon of the next nucleotide.