In a classic monohybrid cross with complete dominance, what is the typical phenotypic ratio?

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Multiple Choice

In a classic monohybrid cross with complete dominance, what is the typical phenotypic ratio?

Explanation:
In a monohybrid cross with complete dominance, only two phenotypes appear for a single gene: dominant and recessive. When true-breeding dominant and true-breeding recessive parents are crossed, all offspring are heterozygous and show the dominant phenotype. If those heterozygous offspring are then crossed with each other, the offspring genotypes follow a 1:2:1 ratio (AA : Aa : aa). Since both AA and Aa express the dominant trait, three out of four progeny show the dominant phenotype and one out of four shows the recessive phenotype. That yields a phenotypic ratio of 3:1.

In a monohybrid cross with complete dominance, only two phenotypes appear for a single gene: dominant and recessive. When true-breeding dominant and true-breeding recessive parents are crossed, all offspring are heterozygous and show the dominant phenotype. If those heterozygous offspring are then crossed with each other, the offspring genotypes follow a 1:2:1 ratio (AA : Aa : aa). Since both AA and Aa express the dominant trait, three out of four progeny show the dominant phenotype and one out of four shows the recessive phenotype. That yields a phenotypic ratio of 3:1.

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