Growth and Form 95 



Fig. 44b. Growth of the 

 chick during its embryonic 

 and post-hatching periods 

 (redrawn fronn Weiss and 

 Kavanau) . 



Fig. 44c. Bacteria are introduced into fresh nutrient broth. At intervals, a 

 sample is abstracted to determine the number of bacteria per cubic cen- 

 timeter of broth. Three phases of the resultant growth curve are recognized: 

 I — lag phase; II — logarithmic phase; III — stationary phase. If, now, bacteria 

 from the stationary phase are used to inoculate another flask of nutrient 

 broth, the growth pattern repeats itself. 



o 100,000,000 



o E 50,000,000 



24 

 Time in hours 



Time in hours 



