. Applied bacteriology for nurses. subdivided according to the manner inwhich the individual organisms tend to group them-selves when multiplying. Thus a large class of coccidivide always in a single plane, and so give rise to astring of cocci appearing like a string of beads. Coccigrowing in this manner are termed streptococci. Inanother large class the organisms divide in every plane,so that there is produced a mass having somewhat theappearance of a bunch of graj^es. Cocci growing in thismanner are termed staphylococci. Other cocci, on multi- 16 APPLIED BACTERIOLOGY FOR NURSES plying, arran
. Applied bacteriology for nurses. subdivided according to the manner inwhich the individual organisms tend to group them-selves when multiplying. Thus a large class of coccidivide always in a single plane, and so give rise to astring of cocci appearing like a string of beads. Coccigrowing in this manner are termed streptococci. Inanother large class the organisms divide in every plane,so that there is produced a mass having somewhat theappearance of a bunch of graj^es. Cocci growing in thismanner are termed staphylococci. Other cocci, on multi- 16 APPLIED BACTERIOLOGY FOR NURSES plying, arrange themselves in groups of two each, andthese are termed diplococci, while still others arrangethemselves in groups of fours, and these are termedtetrads. In medical bacteriology besides bacilli andspirilla, the streptococci, staphylococci, and diplococciplay an important role. In a preceding paragraph it was stated that bacteriamultiphed when placed in proper surroundings. Onthe other hand, tnere is considerable variation in the. Fig. 3.—Bacillus tetani, showing spores. Pure culture on stain (Kolle and Wassermann)• behavior of different species of bacteria when placed inunfavorable surroundings. ]\Iany quickly perish; otherslive for some time, and then gradually die off. Stillothers undergo a peculiar transformation into a highlyresistant form known as spores. A^g^ozig is a round oroval body, usually highly refractive, and possessing ahigh degree of resistance against various destructiveagents. Spores, as such, clo_not multiply, and may,therefore, be compared to seeds. A bacterium produces CHARACTER OF BACTERIA 17 only a single spore. Spore formation is limited to thebacilli. The fact that spores are so resistant is practi-cally important, and necessitates a careful study of theprinciples underlying sterilization. Among the spore-forming bacilli encountered in medicine may be men-tioned the bacillus of tetanus (lockjaw), the bacillus ofanthrax, and the bacillu
Size: 1773px × 1410px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectbacteri, bookyear1919
