Germ theory Idea that microorganisms may cause disease The discovery that

Germ theory idea that microorganisms may cause

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Germ theory Idea that microorganisms may cause disease The discovery that microorganisms, like yeast could cause changes in organic materials alerted scientist to think about the idea that microorganisms could potentially cause changes in plants and animals (us!) Like Biogenesis the Germ theory was a difficult concept for most
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The Germ Theory of Disease 1835: Agostino Bassi showed that a silkworm disease was caused by a fungus. 1865: Pasteur believed that another silkworm disease was caused by a protozoan. 1840s: Ignaz Semmelwise advocated hand washing to prevent transmission of puerperal fever from one OB patient to another.
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Joseph Lister Began applying germ theory to medical procedures He knew that phenol solutions kills bacteria, so he began treating surgical wounds with phenol Reduced infections dramatically Findings proved that microorganisms cause surgical wound infections
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Robert Koch Koch provided the first proof that bacteria causes disease when he discovered Bacillus anthracis caused anthrax He designed a sequence of experimental steps for directly relating a specific microbe to a specific disease
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Koch’s Experiment Microorganisms (MO) are isolated from a dead animal The MO are grown in pure culture and identified Then the MO are injected into a healthy animal The disease is reproduced in the second animal; MO are isolated again MO are grown in pure culture and identified as the same MO from the first dead animal
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From this experiment, Koch derived a set of criteria to discern the origin of a disease Koch’s Postulates
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Koch’s Postulates
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Exception’s to Koch’s Postulates Some microbes have unique culture requirements Treponema pallidum has never been cultured on artificial media Some infectious diseases are not as clear-cut Nephritis can be caused by several MO’s Some MO’s can cause several diseases Streptococcus pyogenes cans cause sore throat, skin infection, and other diseases
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