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Bacteria, why do they make me sick?
What are bacteria?
Bacteria are microscopic organisms that lack a defined or structured nucleus. These organisms are classified as prokaryotes.
Structure of a bacterium
Bacterial cells range in size from 0.5 to 5 μm (1 μm is 0.0001 cm). It has a cytoplasm enclosed by a plasma membrane. The outermost layer is the cell wall that varies depending on the type of bacteria. The bacterial genome consists of a long DNA filament, circular and closed, called nucleoid, which is compacted in the cytoplasm and lacks a membrane. The cytoplasm also contains many ribosomes, and in some cases, inclusion bodies. Some bacterial cells also have a capsule, flagellum and fimbriae (also called pili).
