Class 12th Biology 2016 Set3 Delhi Board Paper Solution
Question 24
What is polygenic inheritance ? Explain with the help of a suitable example.
Answer
Inheritance in which traits are controlled by three or more genes , eg human skin colour / height , the inheritance depends upon the additive / cumulative effect of allelles , more the number of dominant allelles the expression of the trait will be more distinct / prominent , more the number of recessive allelles the trait will be diluted , if member of dominant and recessive allelles are equal the effect is intermediate
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