OUTLINE FOR THE INSTRUCTOR ON THE PREPARATION 

 FOR MICROBIOLOGICAL EXPERIMENTS (EXERCISES VI 

 THROUGH IX) 



APPENDIX A 



A. MATERIALS 



1. Glassware 



Pyrex culture tubes without lips are preferable. 

 They will be needed in three sizes : 1 3 X 100 mm, 

 16 X 150 mm, and 20 X 150 mm. Along with 

 the 5-ml serological pipets and Erlenmeyer 

 flasks, they may be obtained from any scientific 

 supply house. 



Dropper pipets of sufficient length for transfers 

 from tubes (about six inches) are difficult to 

 obtain commercially and probably will have to 

 be made up. Alternatively, 1-ml serological 

 pipets or Pasteur pipets may be used. 



Sterile disposable petri dishes, 15 X 100 mm, 

 available from Falcon Plastics, 5500 West 83rd 

 St., Los Angeles 45, or from Scientific Products, 

 1210 Leon Place, Evanston, Illinois, at a cost of 

 about five cents apiece, are recommended since 

 their use obviates the need for much tedious 

 cleaning, washing, and sterilizing, and also 

 allows the students to take plates home with 

 them to observe growth. 



2. Media and Chemicals 



Ready-mixed media such as nutrient broth, 

 nutrient agar, and tryptose blood agar base can 

 be obtained from Difco Laboratories, Detroit 1, 

 Michigan. They should be made up according 

 to the directions on the bottles. 



Of the constituents for the Pneumococcal 

 media, Casamino acids, tryptone, yeast extract, 

 and brain-heart infusion are obtained from 



Difco. All other organic materials including 

 vitamins, amino acids, sugars, streptomycin, 

 deoxycholic acid, methylene blue, serum albu- 

 min, and sterile horse blood may be obtained 

 from Nutritional Biochemicals, Cleveland, Ohio. 

 Fresh yeast can be procured from Standard 

 Brands, Inc. 



Inorganic chemicals, reagent grade, are avail- 

 able from any chemical supply house. Antifoam 

 may be obtained from the Dow Chemical Com- 

 pany. 



3. Miscellaneous 



a. Constant-temperature equipment 



Water baths may be rigged up from parts 

 which can be obtained at relatively low cost 

 from an aquarium supply house. A tank 

 16" X 10" X 12" deep, fitted with a 100-watt 

 thermostat aquarium heater and a 100-watt 

 constant heating element and either an air line 

 or aquarium bubbler for stirring, will provide 

 room for eight students. However, if at all pos- 

 sible, it is recommended that water baths or 

 their components be obtained from scientific 

 research supply houses in order to achieve more 

 reliable temperature regulation. 



Two neoprene-coated test-tube racks with 

 holes large enough to accommodate tubes 20 

 mm in diameter (obtainable from Emil Greiner 

 Co., New York City) may be supported in the 

 baths by means of platforms made of i" mesh- 

 wire screening. 



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