GENETICS AND EVOLUTION
INHERITANCE AND VARIATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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if the phenotype of offsprings shows only the dominant trait, then the parent plant was homozygote to the dominant trait
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if the offsprings produced are of both phenotypes, then the parent plant was heterozygote to the dominant trait
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both are correct
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None of the above
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Detailed explanation-1: -Testcross is a cross of any genotype showing dominant phenotype with a recessive homozygote to determine the genotype of a dominant parent if it is a heterozygous-or homozygous-dominant. Being a hybrid Tt shows dominant phenotype and tt is the recessive parent; it is a test cross. Option A is correct.
Detailed explanation-2: -In a test cross F1 generation that has a dominant phenotype is crossed with a parent plant that has homozygous recessive genotype or recessive phenotype. Since, the cross is done with the parent individual, it can be considered as a back cross.
Detailed explanation-3: -Solution. Tt × tt is a test cross.
Detailed explanation-4: -Explain the differences between monohybrid and dihybrid crosses. A monohybrid cross occurs when two individuals have homozygous genotypes for the opposite phenotype for a certain genetic trait. A dihybrid cross is a cross between two distinct genes whose observable features differ.