CONTENTS 



Vll 



Exercise 49. To Isolate Spore-forming Bacteria and to Study 



Spore Formation 144 



Exercise 50. To Demonstrate the Efficiency of Filtration as a 



Means of Removing Microorganisms from Liquids 145 

 Exercise 61. To Demonstrate the Presence of Microorganisms in 



Air, on Desk, Floor, etc 146 



Exercise 62. Qualitative Study of the Microorganisms of the Skin 



and Hair , 148 



Exercise 53. Qualitative Study of the Microorganisms of the 



Mucous Membrane ... .... 150 



PART II 



PHYSIOLOGY OF MICROORGANISMS 



Exercise 1. To Demonstrate the Small Amount of Food Needed 



by Bacteria 152 



Some Physiological Classifications of Bacteria 153 



Anaerobic Culture Methods 155 



Exercise 2. The Effect of Anaerobic Conditions upon Micro- 

 organisms from Manure 165 



Exercise 3. To Demonstrate that Acids Are Formed from Car- 

 bohydrates by Bacteria 167 



Exercise 4. To Show that Organic Acids May Serve as a Food 



for Some Organisms 169 



Exercise 5. To Demonstrate the Variation in Food Requirements 



of Bacteria 170 



Exercise 6. To Demonstrate the Splitting of Carbohydrates into 



Alcohol and CO 2 171 



Exercise 7. To Demonstrate the Necessity of Nitrogen in Some 



Form for Microbial Growth 172 



ExerciseS. To Demonstrate the Production of H 2 S by Bacteria. 174 

 Exercise 9. The Effect of Physical and Chemical Agencies on 



Microbial Pigment 175 



Exercise 10. To Illustrate One of the Physical Products of 



Metabolism 177 



Enzymes: Classifications and Reactions 178 



Exercise 11. A Comparison of Acid and Rennet Curds 185 



Exercise 12. To Show the Action of Proteolytic Enzymes upon 



Gelatin . . .187 



