Questions and Problems 201 



b — pr 6 per cent 



cur — rt 7 per cent 



d — pr 24 per cent 



rt—st 7 per cent 



Assume that all other combinations showed 50 per cent crossing over. 

 Plot these genes on their chromosome or chromosomes. (Data are ap- 

 proximate and not based on actual experiment.) 



9. What is a translocation? Of what value are translocations in 

 linkage experiments? 



10. What are the difficulties involved in constructing linkage maps in 

 human beings? Would such maps be of practical value to a physician? 



V 



