c 



Physical Microbiology 



Introduction to Part C 



This section of the text deals with the physical properties 

 of cells and groups of cells as revealed by various bio- 

 physical studies. The first chapter of Part C, Chapter 10, 

 describes cellular events produced by ionizing radiations. 

 This topic is continued in Part D, Chapter 16, "Molecular 

 Action of Ionizing Radiations." Some scientists consider 

 the material in these two chapters as synonymous with 

 biophysics, whereas others feel that the effects of ionizing 

 radiations should not even be considered as part of bio- 

 physics. The emphasis, in Chapter 10, has been placed 

 on the use of ionizing radiations to study the fundamental 

 properties of biological systems. 



Not all radiations are damaging. In Chapter 11, the 

 physical properties of cells and of groups of cells revealed 

 by nondestructive electromagnetic and ultrasonic irradia- 

 tion are discussed. This is followed by two chapters deal- 

 ing with the effects of high intensity ultrasound; the 

 second of these two, Chapter 13, illustrates one of the 

 areas in which advanced mathematical training is helpful. 



The last chapter of Part C is a description of the physico- 

 chemical properties of virus particles. Such particles lie 

 between biological cells and molecules in their complexity 

 and in their physical and chemical properties. The dis- 

 cussion of virus particles is intermediate between the other 

 topics of Part C and the contents of Part D. 



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