Linkage and Crossing Over Between Genes 



123 



METAPHASE I 



B 



TELOPHASE II 



light apricot 

 weak forked 



light apricot 

 weak forked 



34b 



white 

 weak forked 



apricot 

 weak forked 



figure 9-7. Genotypic and phenotypic consequences of no crossing over {A ) and 

 of one type of crossing over (B) between marker genes in an attached-X female of 

 Drosophila. 



