GLOSSARY 209 



Lesion Used to indicate any physical change from normal. 

 Leukocytes The colorless, so-called white cells of the blood. 



Medium (pi., Media) General name given to foodstuffs upon 

 which bacteria are grown artificially. 



Micrococcus The genus of spherical organisms dividing in two 

 planes. , 



Morphology A study of the physical nature, size, and shape of 

 any object. Adj., morphological. 



Nucleus (pi., Nuclei) A mass within a cell clearly outlined from 

 and denser than the cytoplasm or protoplasm, and in which the 

 reproductive powers of the cell probably lie. 



_ l gy_A suffix meaning a "study of" the root, such as mor- 

 phology, which see. 



Opsonins Substances in the blood serum which prepare foreign 

 bodies, usually bacteria, for consumption by the white cells of the 

 blood, the phagocytes. 



Optimum The best, most suitable. 



Organic A substance having the form, the chemistry, or some 

 characteristics of living matter; example, egg white. See Inorganic. 



Parasite An organism living on or in a host to the detriment of 

 the latter. Adj., parasitic. 



Pathogenic Capable of producing disease. 



Pathology The study of disease the broad subject of the cause, 

 production, and result of disease, and especially the changes it 

 produces in the body. Related words : pathologic, -al. 



Phagocytosis The act of consuming foreign bodies, notably 

 bacteria, by the large white cells of the blood, called phagocytes. 

 Adj., phagocytic. 



Plane The geometrical dimension. There is one plane in a line, 

 two planes in a surface, and three planes in a body, suoh as a cube. 



Plasma The fluid part of the blood including the constituents 

 capable of clotting. See Serum. 



Poisons Used generally to indicate any substance dangerous 

 to body. Has no particular significance for bacterial products when 

 used alone. 

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