There are many ways of classifying bacteria. One method is based on the cell membrane. In 1884, a bacteriologist named Christian Gram created a test that could determine if a bacterium had a thick, ...

THE fact that milk affords a particularly suitable medium for the growth and multiplication of most micro-organisms, has rightly led to its being regarded as a dangerous vehicle for the propagation of ...

Nine species (240 strains) of gram-negative bacilli were studied; 221 were freshly isolated from the urinary and intestinal tracts, wounds and abscesses. Thirteen strains of salmonella and 6 of ...

Gram staining is one way scientists can identify bacteria. Gram-positive bacteria, such as Staphylococcus, appear blue or purple under a microscope when scientists apply a stain. Conversely, ...

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