This question is worded weird, because if someone had a dominant phenotype, as in Brown eyes dominant, than they would be BB or Bb. The exact genotype would need to have a key to what one of their parents' genotype was. Example: If a man with brown eyes (dominant) had a mom with blue eyes (recessive) then what would the man's genotype be? the answer would be Bb because that means that the man's dad would have BB and mom would be bb and when using punnent square, his genotype is Bb (only possible genotype is Bb)
The AA genotype typically produces the phenotype associated with the dominant allele A. This means that the dominant trait will be expressed in the individual with this genotype.
The phenotype can tell you the genotype of a trait when the trait is determined by a single gene with clear dominant and recessive alleles. In cases where there is complete dominance, observing the physical expression (phenotype) can provide information about the underlying genetic makeup (genotype) of an individual.
To determine the genotype of an individual that shows the dominant phenotype you would cross that individual with one that is homozygous recessive. A monohybrid cross of two individuals that are heterozygous for a trait exhibiting complete dominance would probably result in a phenotype ratio is 3 dominant 1 recessive.
In a test cross, one individual with a dominant phenotype but unknown genotype is crossed with a homozygous recessive individual. The genotype of the individual with the dominant phenotype can then be inferred based on the phenotypic ratios of the offspring.
An Aa genotype can result in the same phenotype as either an AA or AA genotype, if one of the alleles acts in a dominant fashion. If the A allele is dominant over the a allele, then the phenotype of a heterozygous (Aa) individual will be the same as the phenotype of a homozygous dominant (AA) individual.
testcross
A test cross.
Genotype: AA - The phenotype is homozygous dominant, exhibiting the dominant trait. Genotype: Aa - The phenotype is heterozygous, exhibiting the dominant trait. Genotype: aa - The phenotype is homozygous recessive, exhibiting the recessive trait.
Homozygous dominant genotype (AA): The phenotype will show the dominant trait. Heterozygous genotype (Aa): The phenotype will also show the dominant trait due to the presence of at least one dominant allele. Homozygous recessive genotype (aa): The phenotype will exhibit the recessive trait.
Homozygous recessive.
genotype or phenotype
The phenotype of an individual is ultimately determined by a combination of their genetic makeup (genotype) and environmental factors. Genes provide the instructions for building and maintaining an organism, while the environment can influence the expression of these genes. The interaction between genetics and environment shapes the physical and behavioral characteristics that make up an individual's phenotype.