Bacterial Reproduction

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Bacterial Reproduction
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Introduction

• Bacteria can reproduce in one of two ways
• Asexually
• Sexually

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Asexual Reproduction

• Binary Fission
• one parent involved
• offspring are identical to parent each other
• Advantages
• simple only 1 parent
• offspring are fully formed (no maturation needed)
• very fast (20 min. in ideal conditions)
• after 24 hrs
• 1 bacterium 2x106 kg of cells
• (enough to cover the earth)

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Asexual Reproduction

• Disadvantages
• no genetic variety
• one unfavourable environmental condition can wipe
  out whole population

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Asexual Reproduction
Binary Fission
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Asexual Reproduction
Binary Fission
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Sexual Reproduction

• two parents involved
• offspring are genetically different
• to parents to each other
• Advantages
• genetic variety i.e. some are able to adapt to
  unfavourable conditions (ex antibiotic
  resistance)
• Disadvantages
• more complex slower because must find a
  compatible partner
• no new individuals produced
• (i.e. no increase in population)

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Bacterial Conjugation
donor recipient cell () cell
( - )
plasmid

• plasmid copies itself
• passes through pili (cytoplasmic bridge) into
  recipient cell
• cells separate with both cells containing the
  plasmid

pili
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Homework

• Page 112 4, 5, 7

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Bacterial Conjugation