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INHERITANCE OF TWO OR MORE CHARACTERS 



Mendel crossed a strain that had one character dominant with one that had a differ- 

 ent character dominant — say, a tall green-seeded plant with a dwarf yellow-seeded 

 one. All the offspring had both dominant characters. When the hybrids, Fi, were 

 mated, segregation of the dominant and recessive characters in the ratio of 3 : 1 took 

 place in the following generation, F2, independently for each pair of contrasting 

 characters 



there can be such great diversity among individuals of any given species, or 

 even among the brothers and sisters of any family. The greater the number 

 of characters, the greater is the possible number of combinations, and the 

 smaller is the chance that any given combination will occur again. 



These three laws of heredity — dominance, segregation, and independent 

 assortment — are known as Mendelian laws, or principles, because they were 

 first discovered by Gregor Mendel. 



The Rediscovery of Mendel Gregor Mendel read a paper on the re- 

 sults of his experiments in 1865, and the following year published the paper 

 in the journal of the local scientific society. There it remained in dead storage 

 to the end of the century. For there is no indication that any of the scientists 



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