GENETICS AND EVOLUTION
INHERITANCE AND VARIATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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genes which control continuously variable characters like height, weight, etc.
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multiple copies of a single gene
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always linked genes
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pseudogenes
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Detailed explanation-1: -A polygenic trait is a characteristic, such as height or skin color, that is influenced by two or more genes. Because multiple genes are involved, polygenic traits do not follow the patterns of Mendelian inheritance. Many polygenic traits are also influenced by the environment and are called multifactorial.
Detailed explanation-2: -In polygenic inheritance, each allele has a cumulative or additive effect on the phenotype thus generating continuous variation, e.g. skin pigmentation, height, etc.
Detailed explanation-3: -Continuous variation describes traits whose phenotypes occur on a continuum, rather than having a limited number of possible phenotypes. Traits with continuous variation are often also polygenic traits, but not always, and not all polygenic traits have continuous variation.
Detailed explanation-4: -Examples of polygenic inheritance in humans include traits such as skin colour, eye colour, hair colour, body shape, height, weight etc.