There were several other contributors to the germ theory of disease. Louis Pasteur studied fermentation and developed the swan-neck flask experiment, which proved that some organisms causing bacterial contamination were airborne. Joseph Lister studied postoperative infections and insisted on strict handwashing during surgery. He also developed the concept of using antiseptics for surgical procedures. Robert Koch developed Koch’s postulates, which attributed certain diseases to a specific pathogen. Several infectious diseases, such as cholera, anthrax, and tuberculosis. This was the first incidence of the idea of “one microorganism, one disease”. This completely did away with the miasma theory and supported the germ theory of disease.
THE PROKARYOTIC CELL There are two different types of cells, which are very different from one another. All cells will have a cell membrane, regardless of the type. All will have cytoplasm, which is the watery component of the cell; all will have some type of nucleic acid or genetic material and all will have ribosomes. These components will be there whether the cell is prokaryotic or eukaryotic. Beyond this, however, prokaryotic cells and eukaryotic cells are very different from one another. In general, eukaryotic cells are larger than prokaryotic cells. Prokaryotic cells, compared to eukaryotic cells, are relatively simple and they do not have membrane-bound organelles. There are some inclusions that help to compartmentalize the cells. Figure 11 depicts what a typical prokaryotic cell looks like:
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