1SS CHAPTER 13 



] 3.9. Compare the number and fate of breakages induced b) the same dose of X rays 

 administered to: 



(a) A polyploid and a diploid liver cell m man 

 (h) A diploid neuron in man and Drosophila 



(e) A sperm and a spermatogonium in man 



13.10. Discuss the importance of the nonmutant effects ol a given dose of radiation 

 upon the mutation frequency induced b\ a subsequent radiation dose. 



13.11. Using Figure 13-4. discuss the likelihood of crossing over in different regions 

 of the X chromosome of D. melanogaster, 



13.12. Compare the roentgen unit with the rad unit. 



13.13. What specific aspects of our present environment tend to reduce the number 

 of mutations induced by penetrating radiations from the number induced when 

 man first evolved? 



