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The Charolais is the second-most numerous cattle breed in France after the Holstein Friesian and is the most common beef breed in that country, ahead of the Limousin.At the end of 2014, France had 4.22 million head of Charolais, including 1.56 million cows, down 0.6% from a year earlier.
Bacteria (prokaryotes, together with Archaea) share many common features. These commonalities include the lack of a nuclear membrane, unicellularity, division by binary-fission and generally small size. The various species can be differentiated through the comparison of several characteristics, allowing their identification and classification.
Bacteria display a large diversity of cell morphologies and arrangements. Bacterial cellular morphologies are the shapes that are characteristic of various types of bacteria and often key to their identification. Their direct examination under a light microscope enables the classification of these bacteria (and archaea).
Consequently, the need to identify human pathogens was a major impetus for the development of techniques to identify bacteria. [177] The Gram stain, developed in 1884 by Hans Christian Gram, characterises bacteria based on the structural characteristics of their cell walls.
Bacteriology is the study of bacteria and their relation to medicine. Bacteriology evolved from physicians needing to apply the germ theory to address the concerns relating to disease spreading in hospitals the 19th century. [5] Identification and characterizing of bacteria being associated to diseases led to advances in pathogenic bacteriology.
Gram staining is almost always the first step in the identification of a bacterial group. While Gram staining is a valuable diagnostic tool in both clinical and research settings, not all bacteria can be definitively classified by this technique. This gives rise to gram-variable and gram-indeterminate groups.
The manual was published subsequent to Bergey's Manual of Determinative Bacteriology, though the latter is still published as a guide for identifying unknown bacteria. [1] First published in 1923 by David Hendricks Bergey , it is used to classify bacteria based on their structural and functional attributes by arranging them into specific ...
Examining colonial morphology is the first step in the identification of an unknown microbe. The systematic assessment of the colonies' appearance, focusing on aspects like size, shape, colour, opacity, and consistency, provides clues to the identity of the organism, allowing microbiologists to select appropriate tests to provide a definitive ...