PATHOLOGY MCQ
GENETICS AND DISEASE
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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many genes
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single genes
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3 genes
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no genes
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Detailed explanation-1: -Definition. 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: -Polygenic traits are traits that are controlled by multiple genes instead of just one. The genes that control them may be located near each other or even on separate chromosomes. Because multiple genes are involved, polygenic traits do not follow Mendel’s pattern of inheritance.
Detailed explanation-3: -Polygenic inheritance occurs when one characteristic is controlled by two or more genes. Often the genes are large in quantity but small in effect. Examples of human polygenic inheritance are height, skin color, eye color and weight. Polygenes exist in other organisms, as well.