56 PHARMACEUTICAL BACTERIOLOGY 



4. General Physiology of Microbes 



Microbes, in common with living things generally, spring from pre- 

 existing parents, take in and assimilate food, grow and multiply, and finally 

 die. The rate of growth and of multiplication (septation or division) 

 varies somewhat, depending on temperature, moisture, and food supply. 

 The average life of one individual (from division to division) is perhaps 

 thirty minutes. Under favorable condition the period is much shortened. 

 This life period of the individual cell must not be confounded with the life 

 cycle of the individuals resulting from a single cell or parent. It is known 

 that under uniform conditions of temperature, moisture, food supply, and 

 the environment generally, the progenations from a single parent cell 



a 



PIG. 10. Illustrating zooglea formation, a, bacillar aggregates resulting from 

 cohesion; b, aggregates resulting from cohesion of bacilli with gelatinized cell-walls; c, 

 streptococcus formation resulting from the septation of a coccus form; d, cohering cocci 

 forms; e, bacilli united end to end (resulting from septation), enclosed in a gelatinous 

 coat;/, bacillar thread enclosed in gelatin; g, mycobacterial form; h, irregular cell forms, 

 as Mycoderma aceti. 



show an increasing rate of septation, a stationary period, followed by a 

 gradual decline, ending in total cessation of all septation, and in death. 

 These life cycles have not yet been carefully determined; in fact, they are 

 but little understood. It is highly probable that the cycles of existence 

 play a very important part in the course and development of diseases of 

 bacterial origin. 



