Early scientists believed living matter could form spontaneously from nonliving matter. This was called spontaneous generation. To support their theory of spontaneous generation, scientists observed that if raw meat was left out in open, white maggots would appear “spontaneously”. Louis Pasteur hypothesized that living matter could not develop from nonliving matter. His experiment compared sterilized broth which he placed in two different shaped flasks. One flask had a straight tube, and the other had a s-curved tube as pictured below.
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Both tubes were open to expose the broth to the air. Pasteur observed that after several days the broth in the flask with the straight tube was cloudy and the broth in the flask with curved tube was unchanged. After testing, the cloudy broth had been contaminated with bacteria from the air. Pasture theorized that the bacteria could simply move easily to the broth through the straight tube, but the bacteria was trapped in the u-shaped area of the curved tube and could not get to the broth. His conclusion provided evidence to disprove the idea that living matter could spontaneously form from non-living matter.
Pasteur’s experiment is viewed as modern scientific inquiry. Which of the following elements of his discovery are necessary for scientific inquiry?
I. l. Begins with a hypothesis
II. ll. Tested with a controlled experiment
III. lll. All parts of the scientific method were followed in order.