MendeVs Law 



47 



Fig. 5 shows that we are deaUng witli two homozy- 

 gotes, each producing only one kind of gamete, so that 

 all the F, progeny are similar, both phenot>pically and 



Gametes 



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Fig. 5. — Diagram illustrating ciihybrid ratio. Upper part shows 

 how original parents were crossed to give Fi hyi)ri(l; lower i)art shows 

 Fi hybrid producing four kinds of gametes; chance matings among these 

 gametes, when Fi is inbred, results as indicated in the large set of squares 

 and explains the 9:3:3:1 ratio in the Fa generation. 



