Number of major DNA molecules in bacteria are

Options

A. One
B. Two
C. Three
D. Many

Answer

To determine the number of major DNA molecules in bacteria, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding DNA in Bacteria**:
- Bacteria primarily contain DNA, which is a polymer of deoxyribonucleotides.
- The DNA in bacteria is typically single and circular in structure.

2. **Characteristics of Bacterial DNA**:
- Bacterial DNA is double-stranded.
- It serves as the main genetic material for the bacterium.

3. **Identifying the Major DNA Molecule**:
- The main genetic material in bacteria is the chromosomal DNA, which is a single circular DNA molecule.
- This chromosomal DNA is essential for the survival and reproduction of the bacteria.

4. **Considering Additional DNA**:
- In addition to chromosomal DNA, bacteria may also contain plasmids, which are small, circular, extra-chromosomal DNA molecules.
- Plasmids are not considered major DNA molecules as they are non-essential and serve additional functions, such as antibiotic resistance.

5. **Conclusion**:
- Since the question asks for the number of major DNA molecules, we focus on the chromosomal DNA.
- Therefore, the number of major DNA molecules in bacteria is **1**.

### Final Answer:
The number of major DNA molecules in bacteria is **1**.

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