An Introduction to a Biology 



Generation. 



1. 



2. 



3. 



4. 



D. 



DR. 



li. 



1 2 1 



(4+2 4 2+4) 



6 4 6 



(24+4 8 4 + 24) 



28 



28 



8 

 (112 + 8 16 8 + 112) 



Ratios. 

 D. DR. R . 



120 



120 



5. 



16 



(480 + 16 32 16 + 480) 



496 



32 



496 



15 



15 



31 



31 



this generation 1,023 with constant dominant character, 

 1,023 with the recessive character, and only two hybrids " 

 (Bateson, '02, p. 59). 



(4) Mendel's Theory to Account for his Results 



Mendel knew that green-seeded peas bred true, when 

 self-fertilised or cross-fertilised by other green peas ; and 

 that the same was true of the yellow. That is to say, the 

 germ-cells of green peas will always produce green peas, 

 and those of yellow will continue to give yellow. 



But what happens when a green pea is crossed with. 

 a yellow : that is, when a " green " germ-cell meets a 

 '' yellow " germ-cell ? We know that a yellow-seeded 

 hybrid is produced ; but we want to know the condition of 

 its germ-cells. Mendel's hypothesis was that it contained 

 50% " yellow " germ-cells and 50% " green " ; no " greenish- 

 yellow " and no " yellowish-green " germ- cells, but equal 



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