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Binary fission is the fundamental division process by which bacteria reproduce. Unlike the complex mitotic cycles of eukaryotes, a single bacterial cell simply doubles and splits into two genetically identical daughter cells.
1. DNA replication – The circular chromosome is duplicated, ensuring each future cell receives a complete genome.
2. Segregation – The two copies migrate to opposite poles of the rod‑shaped cell.
3. Septum formation – Proteins assemble at the mid‑cell, drawing the cell membrane inward.
4. Cytoplasm division – The internal fluid is partitioned evenly between the halves.
5. Cell wall synthesis – A new peptidoglycan layer is laid down, sealing each daughter cell.
From a microbial standpoint, binary fission offers speed and simplicity: a single cell can produce two viable progeny in as little as 20 minutes under optimal conditions. For clinicians, the uniformity of bacterial populations simplifies pharmacological strategies—one antibiotic can target all cells equally. However, the very efficiency of replication also accelerates the emergence of resistance mutations, posing a growing challenge to public health.
