Binary Fission

• Prokaryotic cells can reproduce using a simple cell division called binary fission.
• 1. the circular DNA and plasmids replicate.
  2. The cell gets bigger and the circular DNA strands move to opposite ends of the cell.
  3. The cytoplasm begins to divide and new cell walls begin to form.
  4. The cytoplasm divides and two daughter cells are produced. Each daughter cell has one copy of the circular DNA but can have a variable number of copies of the plasmids.
• Bacteria can divide very quickly if given the right conditions. E.coli can take as little as 20 minutes to replicate in the right environment. However in conditions become unfavourable, the cells will stop diving and eventually die.
• The best conditions for binary fission are warmth and lots of nutrients.
• You can calculate the number of bacteria in a population

  • The mean division time is the average amount of time it takes for one bacterial cell to divide into two. If you know the mean division time of a cell, you can work out how many times it has divided in a certain amount of time, and the number of cells produced in that time.
• A bacterial cell has a mean division time of 30 minutes, how man cells will it have produced after 2.5hrs?

  2.5 hours x 60 = 150 minutes

  150 minutes/30 minutes = 5 divisions

  2^5= 32 cells.