36 CELL STRUCTURES 



Its characteristics are so markedly different, however, that 

 the function of preservation is certainly the main one. 



It is a viistaken idea that spores are formed under adverse 

 conditions. Bacteria require just as exact conditions for syore 

 formation as they do for growth and other functions (Chapters 

 VI and VII). It is true that when the bacterium has 

 changed to the spore stage the s2)ore ivill resist adverse condi- 

 tions much better than the bacterium in its growing stage. 



It is also a mistake to believe that most disease-producing 

 organisms are spore formers. In Ohio and most of the 

 Northern States lock-jaw and an occasional case of ''gas 

 gangrene' are almost the only diseases in man due to spore- 

 forming bacteria. The author knows of only two cases of 

 anthrax (caused by a spore-forming bacillus) in man in his own 

 state. The organism which causes "botulism," a type of 

 toxic food poisoning, is a spore former, but it does not grow in 

 the body and cause disease. 



With the above exceptions not one of our common diseases is 

 caused by a spore-forming organism and hence the organisms 

 are very easily killed. 



