Cell Division

• Bacteria are prokaryotes, their genetic information is not enclosed in a nucleus
• Binary fission


  The process where one bacterial cell splits into two bacterial cells
• Bacteria can carry out binary fission once every 20 minutes as long as they have enough nutrients and the temperature is suitable
• Calculating the number of bacteria after a given time

  1. Calculate the number of rounds of division

  2. Use the equation: Number of bacteria = 2^n, where n is the number of rounds of division

  3. Express the answer in standard form (if required)
• Mitosis


  The process by which a cell divides into two or more cells
• Cell


  • Contains a nucleus
  • Contains chromosomes made of DNA
• Body cells contain 23 pairs of chromosomes
• Gamete cells have unpaired chromosomes
• Chromosome


  Carries a large number of genes that determine many features
• Animals and plants contain a very large number of cells
• Cell cycle including mitosis


  1. DNA replication

  2. Mitosis

  3. Cell division
• Mitosis


  • One set of chromosomes is pulled to each end of the cell
  • The nucleus also divides
  • The cytoplasm and cell membrane divide to form two identical cells
• Functions of mitosis


  • Essential for growth and development of multicellular organisms
  • Repairs damaged tissues
  • Occurs during asexual reproduction