Class 12th Biology 2017 Set2 Outside Delhi Board Paper Solution
Question 25
Explain Polygenic inheritance and Multiple allelism with the help of suitable examples.
Answer
Polygenic inheritance: It is the inheritance of a characteristic that is controlled by more than one gene. Polygenic inheritance can produce unexpected phenotypes.Phenotypes that don't fit with Mendel's expected outcomes based on independent assoectment of dominant and recessive alleles.
Two examples of Polygenic inheritance are:
1 Skin colour in humans
2. Height in humans
Multiple allelism: In this more than one alleles governs the same character and phenotype.
Example: Human blood group (ABO system) controlled by three alleles (IA, IB and i)
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