EVOLUTION
EVOLUTION OF A POPULATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a trait controlled by two or more genes.
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a trait controlled by a single gene that has two alleles.
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a trait controlled by exactly 3 alleles.
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a trait controlled by more than four genes.
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Detailed explanation-1: -If expression of a trait requires only one copy of a gene (one allele), that trait is considered dominant. If expression of a trait requires 2 copies of a gene (2 alleles), that trait is considered recessive. One exception is X-linked disorders.
Detailed explanation-2: -In general one gene effect a single phenotype or trait. However there are instances where a single gene can exhibit multiple phenotypic expression. Such a gene is called a pleiotropic gene and the phenomenon is known as pleiotropy.
Detailed explanation-3: -Polygenic Trait 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.
Detailed explanation-4: -Assuming that you’re referring to single-gene traits, a single-gene trait is a trait that is controlled by only one gene. An example in humans is whether you have a widow’s peak-your hairline forming a small point over the middle of your forehead-or not.