1. Bacteria cannot reproduce without a source of energy and the building blocks of cellular constituents (e.g. amino acids, carbohydrates, lipids).
  2. Minimum requirements for growth are a source of carbon and nitrogen, an energy source, water and various ions. Iron is also an important requirement.


  1. Growth requirements and products of metabolism are often used to classify bacteria
    • Autotrophs: can use inorganic chemicals for their energy and carbon source.
    • Heterotrophs: require organic carbon sources.
    • Need to know these specific requirements to culture successfully for lab diagnostic tests.
    • Some bacteria are obligate intracellular parasites and cannot be cultured in the absence of a eukaryotic cell host.

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