PHENOMENA OF INHERITANCE 



3 2 7 



1. Results of Crossing Individuals with one Contrasting Character. 

 — Having determined that these characters were constant for certain 

 varieties or species Mendel then proceeded to cross one variety with 

 another, by carefully removing the unripe stamens, with their pollen, 

 from the flowers of one variety and dusting upon the stigma of such 

 flowers the pollen of a different variety. In this way he crossed vari- 



PARENTS 





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Fig. 50. Diagram Showing the Results of Crossing Yellow-seeded (Lighter 

 Colored) and Green-seeded (Darker Colored) Peas. From Morgan after 

 Thompson.) 



eties of peas which differed from each other in some one of the charac- 

 ters mentioned above, and then studied the offspring of several succes- 

 sive generations with respect to this character. 



In every case he discovered that the plants that developed from such 

 a cross showed only one of the two contrasting characters of the parent 

 plants, i. e., all were round-seeded, yellow seeded, tall, etc., although one 

 of the parents had wrinkled seeds, green seeds, or short stem, etc. 



Those characters which are transmitted entire or almost unchanged in the 

 hybridization are termed dominant and those which become latent in the process, 

 recessive. 



