DNA replication in bacteria occurs

Options

A. during S phase
B. within nucleolus
C. prior to fission
D. just before transcription

Answer

### Step-by-Step Solution

1. **Understanding DNA Replication**: DNA replication is the biological process through which a cell makes a copy of its DNA. This is essential for cell division and is crucial for the transmission of genetic information to the next generation.

2. **Identifying the Context**: In bacteria, which are prokaryotic organisms, DNA replication is different from that in eukaryotic cells. Bacteria do not have a defined nucleus, and their DNA is typically circular.

3. **Phases of Bacterial Cell Cycle**: Bacteria undergo a simple cell cycle that includes growth, DNA replication, and division (fission). The key point here is that DNA replication must occur before the cell divides.

4. **Fission in Bacteria**: Fission is the process by which bacteria divide. For a bacterium to successfully divide, it must first replicate its DNA so that each daughter cell receives a complete copy of the genetic material.

5. **Role of Mesosomes**: In bacteria, mesosomes are structures that are believed to be involved in the replication of DNA. They help in the segregation of the replicated DNA into the daughter cells during division.

6. **Conclusion**: Based on the understanding that DNA replication occurs before the cell divides (fissions), the correct answer to the question is that DNA replication in bacteria occurs prior to fission.

### Final Answer
**C) Prior to fission**

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