Bacterial Reproduction (Leaving Cert Biology): Revision Notes

Bacterial Reproduction

• Bacterial reproduction is asexual.
• The process is called binary fission.

Binary Fission

1. DNA replicates and the cell elongates.
2. The two identical pieces of DNA move to opposite ends of the cell.
3. Ingrowths form in the cell wall.
4. The cell splits in two (cytokinesis) and two identical cells are formed.

• In suitable conditions, bacteria can reproduce every 20 minutes.
• Due to this rapid reproduction, mutations can pass quickly from one generation to the next.

Endospores

• When conditions are unsuitable (e.g.extreme temperatures), bacteria can produce endospores which can survive harsh conditions.
• Endospores are:
  • Thick, tough-walled, dormant bacterial cells.
  • Able to survive for up to 100 years.
• When conditions become suitable again, the endospore absorbs water, the tough wall breaks and binary fission (bacterial reproduction) resumes.