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Inheritance and Variation — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYInheritance and Variation4 Marks
Question
Distinguish Between: Incomplete dominance and Co$-$dominance.
✓

Answer

Incomplete dominance Co-dominance
$1.$ Incomplete dominance is seen when the phenotypes of the two parents blend together to create a new phenotype for their offspring. $1.$ Co$-$dominance is seen when the two parent phenotypes are expressed together in the offspring.
$2.$ Both the genes of an allelomorphic pair express themselves partially in $F_1$ hybrids. $2.$ Both the genes of an allelomorphic pair express themselves equally in $F_1$ hybrids.
$3.$ In incomplete dominance, a mixture of the alleles in the genotype is seen in the phenotype. $3.$ In co$-$dominance, both alleles in the genotype are seen in the phenotype.
$4.$ The phenotypic effect of one allele is more prominent than the other. $4.$ The phenotypic effect of both the alleles is equally prominent.
$5.$ Blending or intermixing of two alleles can be observed. A white flower and a red flower alleles mix and produce pink flowers.Example : Pink flowers in Mirabilis jalapa. $5.$ No intermixing or blending effect of two alleles is observed. The colours don’t mix but are seen in patches.Example : Roan colour in cattle.

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