9781422277652

The French microbiologist Louis Pasteur showed that tiny organisms carried diseases and could spread them from one infected person or animal to another. His germ theory of disease is one of the most im- portant ideas in medicine and other life sciences.

dimorphic— a substance that exists in two different structural forms. Ecole Normale— a school in Paris where teachers were trained. polarized light— light that has been altered by being passed through a crystal or solution, so that its rays all travel in the same plane. tartaric acid— an organic acid found in wine and other substances. Words to Understand