
Concept explainers
How did Louis Pasteur help disprove spontaneous generation?

To review:
The contribution made by Louis Pasteur to disapprove spontaneous generation.
Introduction:
The spontaneous generation refers to an obsolete thought of the process of generation of living organisms from the non-living or sterile matter.
Explanation of Solution
The idea of spontaneous generation was challenged by many scientists. In 1861, Louis Pasteur performed some experiments to disapprove belief of spontaneous generation of living organisms from the sterile or nonliving materials. He demonstrated presence of microorganisms in the air by trapping microbes on passing air from the cotton plug. After that, he investigated trapped organisms and later cultured those microbes by dipping cotton plug in a sterile broth (solution containing all growth nutrients).
He also performed an important scientific experiment with a self-constructed swan-necked flask filled with a sterile broth. He demonstrated that sterile broth remained sterile even when flask was left open for years. This is so as the microorganisms present in the air settled down at the bends of the flask’s necks and did not reach broth to grow. But as soon as the flask was tilted, the broth reached the settled microbes and their growth was observed.
Therefore, these experiments of Pasteur led to the exemption of the idea of spontaneous generation. The concept of biogenesis, that is, origin of living things from other living things, came into light.
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Chapter 1 Solutions
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