SEX AND GENES 



217 



When an FF egg and an MM sperm are brought together 

 a tetraploid sporophyte (FFMM) is produced. 



When the FF ovule is fertilized by a normal male 



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o 



2 



5 



-5 







7^ 



o 



W// *S 



A 



/ \ 



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^ 

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^ 



^ 

 ^ 

 ^ 



^<f_ ' 



T 



^ 

 ^ 



V 



V 



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Fig. 125. 



Diagram illustrating different combinations of diploids and 



triploid mosses. (After Wettstein.) 



sperm cell M, a triploid sporophyte (FFM) is produced. 

 Thus: 



M 



\ 



FFM 



FF 

 / \ 



MM 



FFMM 



From each sporophyte, FFM and FFMM, a gametophyte 

 can be regenerated. Each of these plants develops both 



