| 
                                Mendel began his
                                research well
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                              | 
                                prepared with
                                cross experiments
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                              | 
                                 on simple
                                features.
                                 | 
                            
                            
                              | 
                                 This way he proceeded
                                to gradually
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                              | 
                                
                                more complex experiments. He 
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                              | 
                                 also worked with
                                repeatable 
                                 | 
                            
                            
                              | 
                                 experiments. Experiments, for that 
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                              | 
                                
                                matter, that also led to quantitative
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                              | 
                                
                                results.
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                              | 
                                This
                                practice of science so common
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                              | 
                                nowadays
                                was not so usual at all at 
                                 | 
                            
                            
                              | 
                                 that time.
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                              | 
                                       
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                              | 
                                Mendel wanted to be
                                certain,
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                              | 
                                before starting his
                                cross
                                 | 
                            
                            
                              | 
                                experiments, that his
                                material to
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                              | 
                                begin with would be homozygous
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                              | 
                                (pure breed).
                                 | 
                            
                            
                              | 
                                And indeed, it took
                                already some 
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                              | 
                                time 'only' to produce
                                this
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                              | 
                                material before he
                                actually could
                                 | 
                            
                            
                              | 
                                do the first crosses.
                                 | 
                            
                            
                              | 
                                (One could call this way
                                to proceed 
                                 | 
                            
                            
                              | 
                                
                                easily also a method of 
                                "Technological
                                 | 
                            
                            
                              | 
                                Design"- avant la  lettre ...)
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