Category: B

Slide for approximate counts of bacteria in fluids (especially milk), the slide being ruled in plain centimetre squares.  

Dried serum albumin fraction which, reconstituted and added to culture medium, provides nutriment and (in the case of fluid cultures of MyCO. tuberculosis’) enhances growth by protecting the organisms from toxic growth products.  

Commensal spirochaete of anal and genital mucous membranes, highly refractile and actively motile.  

Causative organism of European relapsing fever, the spirochaete is 10-20Mm long with fairly regular coils, and is demonstrable in Romanovsky stained films, wet blood films, and by Gram’s method. The spirochaete is cultivated—though not easily—in a variety of media containing animal protein such as serum or blood. It is transmitted to man by body lice.…

Infective agent of West African relapsing fever, Borr. duttonii is morphologically similar to Bon. recurrentis, but is a separate species, transmitted by ticks. The causative agent for East African tick-borne relapsing fever. Other causes of endemic relapsing fever include Borrelia hermii.  

The genus of spirochaetes which (compared with the treponema and leptospira) are larger (up to 30μm), more refractile, stain by conventional methods, and possess open coils of large wave-length. Both commensal and pathogenic species occur, and some are cultivable on special media. Borrelia, a group of bacteria characterized by their spiral shape, are transmitted through…

Nutrient digest or infusion agar plus 5-10 per cent blood (of horse usually), oxalated or defibrinated, added at 55 C. Employed nutritionally for the cultivation of fastidious microbes, but also as an indicator of haemolysis caused by colonial growth products. Chocolate agar is formed by heating set blood agar plates at 60° C for an…

Bacterial staining phenomenon in which the ends of the cell are more deeply coloured than is the central portion.  

Means of differentiating Str. pneumoniae from Str. viridans, a broth culture of the former being soluble in bile (10 per cent sodium taurocholate). A variation of the test uses sodium desoxycholate solution instead of bile. The tests have been largely superseded by the optochin test.  

A constituent of normal mammalian serum possessing bactericid.al qualities against some Gram-positive organisms.