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3.4 perform an investigation to model Pasteur’s experiment to identify the role of microbes in decay

perform an investigation to model Pasteur’s experiment to identify the role of microbes in decay

Pasteur’s experiment

  • When Pasteur did his experiment, the broth in the swan-necked flask remained clear for several weeks, while that in the open flask quickly became cloudy and smelly.
  • Both flasks were open to the air. In the swan-necked flask, air could move freely through the neck of the flask just as it did in the straight-necked flask, but the much heavier micro-organisms, in the air, were trapped in the bottom part of the S-curve.
  • This experiment showed that for the broth to grow micro-organisms and start to decay, there had to be access to air containing the spores of micro-organisms.

Pasteur’s experiment (external website)