During the production on r-DNA the use of DNA ligase forms

Options

A. Peptide bonds
B. Phosphodiester bonds
C. Ionic bonds
D. Hydrogen bonds

Answer

**Step-by-Step Text Solution:**

1. **Understanding Recombinant DNA Technology**: Recombinant DNA (r-DNA) technology involves combining DNA from different sources to create new genetic combinations. This process requires various enzymes, including restriction enzymes and DNA ligase.

2. **Role of DNA Ligase**: DNA ligase is an essential enzyme in recombinant DNA technology. Its primary function is to join DNA fragments together. It does this by forming covalent bonds between the sugar-phosphate backbones of the DNA strands.

3. **Types of Bonds**: In the context of DNA, there are several types of bonds:
- **Peptide Bonds**: These are bonds that link amino acids together in proteins.
- **Phosphodiester Bonds**: These are the bonds that form the backbone of DNA, connecting the 5' phosphate group of one nucleotide to the 3' hydroxyl group of another.
- **Ionic Bonds**: These are electrostatic attractions between oppositely charged ions.
- **Hydrogen Bonds**: These are weak bonds that occur between complementary nitrogenous bases in DNA.

4. **Identifying the Correct Bond**: In the production of recombinant DNA, DNA ligase specifically facilitates the formation of phosphodiester bonds between the DNA fragments. This is crucial for creating a stable and continuous DNA molecule.

5. **Conclusion**: Therefore, during the production of recombinant DNA, the use of DNA ligase forms phosphodiester bonds between the DNA fragments.

**Final Answer**: The use of DNA ligase during the production of recombinant DNA forms **phosphodiester bonds**.

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