Incomplete Dominance ||Class 12 Biology

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     Incomplete Dominance is defined by Carl Correns. It is a phenomenon in which the F1 hybrid shows intermediate characters of the parental genes. In incomplete dominance, the phenotypic ratio deviates from the normal Mendel's monohybrid ratio. Characters are not blending in F1 generation because parental types are recovered in F2 generation.
      Example: Flowers colour in Mirabilis jalapa or 4 o' clock plant and Snapdragon or Antirrhinnus sp. 
       In a cross between red flower (RR) and white flower (rr) plant, the F1 generation obtained was pink (Rr). Again, when the same F1 progeny was self-pollinated, the F2 resulted in the ratio 1:2:1, i.e. not 3:1.




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