. Microbes & toxins. Bacteriology; Toxins; Antitoxins. FORM AND STRUCTURE OF MICROBES 55 Bacteria—The term "microbes" in current language most frequently signifies bacteria. The bacteria belong to the lower plants, are unicellular, contain no chlorophyll, and are almost all incapable of taking up carbon from the carbonic acid of the air. They are incapable of life except in the presence of ready made organic matter, and are in consequence confined either to a saprophytic existence (moulds on a fruit) or to a parasitic (as in the case of the typhoid bacillus in the intestine). Sca
. Microbes & toxins. Bacteriology; Toxins; Antitoxins. FORM AND STRUCTURE OF MICROBES 55 Bacteria—The term "microbes" in current language most frequently signifies bacteria. The bacteria belong to the lower plants, are unicellular, contain no chlorophyll, and are almost all incapable of taking up carbon from the carbonic acid of the air. They are incapable of life except in the presence of ready made organic matter, and are in consequence confined either to a saprophytic existence (moulds on a fruit) or to a parasitic (as in the case of the typhoid bacillus in the intestine). Scattered as they are throughout nature the bacteria are the chief agents in the decompositions and re- combinations of organic and living matter. The usual classification of bacteria depends on their external form and is merely provisional. The round bacteria are called micrococci or cocci. The streptococci are, as Pas- ^ teur described them, like • , rosaries or necklaces; the staphylococci are like bunches of grapes. Ac- cording as the micrococci in their multiplication J. .J . ^ ., Fig. 24.—Principal bacterial forms. I. divide in two or three ^ Strepto- planes in space, they ap- cocci.—4. Staphylococci.—5. Sar- „„„. „„^«j ;« tV-Q .^,,1 cinK.—6., Bacteria.—7. Bacilli.— pear arranged m the mul- g Spiro- berry form or in the form Clostridium. of a sarcina or woolpack. The bacilli are long bacteria, the ends of which are sharply cut; the bacterium., properly speaking, has the ends rounded like a spindle or shuttle. The curved bacteria are known as vibrios, spirilla, and spirochsetes. The bacterial cell is clothed by a membrane and is not naked like an amoeba. It is this sheath, resistant and elastic up to a certain point, which permits a corkscrew spirillum to maintain its form in spite of its movements, and the motile and flexible bacteria to recover their shape after distortion. The
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectantitox, bookyear1912
