EVOLUTION
HARDY WEINBERG EQUILIBRIUM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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all of dominant phenotype
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a quarter of them with recessive phenotype
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all homozygous dominant
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all homozygous recessive
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Detailed explanation-1: -Because homozygous dominant and heterozygous individuals are phenotypically identical, the observed traits in the F2 offspring will exhibit a ratio of three dominant to one recessive.
Detailed explanation-2: -For example, if one parent is homozygous dominant (WW) and the other is homozygous recessive (ww), then all their offspring will be heterozygous (Ww) and possess a widow’s peak.
Detailed explanation-3: -The test cross is another fundamental tool devised by Gregor Mendel. In its simplest form, a test cross is an experimental cross of an individual organism of dominant phenotype but unknown genotype and an organism with a homozygous recessive genotype (and phenotype).
Detailed explanation-4: -In a test cross with a plant of genotype AA all offspring will have the dominant phenotype and will have the heterozygous genotype Aa. However, if a plant with genotype Aa is used in a test cross, then the genotypes of 50% of the offspring will have the genotype Aa and display the dominant trait.