252 Discussion Questions — Part C 



DISCUSSION QUESTIONS— PART C 



1. A table on page 188 in Chapter 10 gives a list of the relative biological 

 effectiveness (RBE) of various types of ionizing radiations. How was each 

 of these determined ? Illustrate your answer with pertinent data. 



2. What are the gross somatic (body) effects of high doses of ionizing 

 radiations in mammals? Relate these insofar as possible to the material of 

 Chapter 10. 



3. Review the evidence for and against the one-gene, one-enzyme hypo- 

 thesis. Indicate how ionizing radiations have been used as a study tool in 

 testing this hypothesis. 



4. Describe the construction of an ultraviolet microbeam apparatus for 

 the irradiation of small parts of living cells. Explain its use by describing 

 two experiments made possible by this apparatus. 



5. Derive the equations for the lines of flow of electric current through 

 (and around) a spherical biological cell model which is suspended in a con- 

 ducting medium, subjected to an electric field having plane symmetry at long 

 distances from the cell. Sketch the lines of current flow in the various fre- 

 quency regions of interest. 



6. Attempts have been made to calibrate electromagnetic diathermy 

 apparatus with nonliving analogs. Describe one of these in detail. How 

 well did the analog mimic the in situ heating ? 



7. Describe ultrasonic equipment suitable for the irradiation of humans. 

 Give some measure of the intensities used. What specific disorders are 

 treated in this fashion ? Present data to indicate the success of the treatment. 



8. Ultrasonic techniques have been used to determine the structures, both 

 hard and soft, within a living human. Basically, this depends on a sonar type 

 of measurement. Describe the equipment used and the results obtained. 

 Compare these with X-ray data. 



9. E. F. Gale has used ultrasonic cavitation to rupture Staphylococcus aureus 

 in order to study the role of nucleic acids in enzymatic synthesis in cell-free 

 systems. Review his findings about the synthesis of enzymes. 



10. W. Nyborg and his associates have emphasized the role of micro- 

 streaming near cavitating nuclei. Describe their theory and experimental 

 results, and the possible significance of this phenomenon in the disruption 

 of single cells in cavitating ultrasonic fields. 



11. Lamb developed the theory for the vibration of solid closed shells in 

 air. Outline his analysis and apply it to biological cells. 



