How do dominant and recessive alleles affect pheno type?

Answer 1

An allele can effect the phenotype of an organism by its dominance or recessiveness. If two dominant alleles are crossed the offsprings will carry the dominant trait of the alleles. If a dominant allele is crossed with recessive allele the phenotype of the offsprings will be of that of the dominant allele. And if two recessive alleles are crossed the phenotype of their offsprings will carry the reccesive trait.

Answer 2

Phenotype is the physical appearance of something, for example red flowers or white fur. Dominant and recessive traits do affect phenotype. Based on the trait that shows, the outcome of the phenotype of the organism varies. For example, R, being the dominant allele for red plants, and r, being the recessive for white plants. If the genes are "RR" or "Rr" then the plant turns out red. If it inherits recessive alleles, then it turns out white, which is the recessive trait. So, based on the dominance and the recessiveness, the phenotype is affected.

Answer 3

In codominance, in which an organism is heterozygous for a trait, both phenotypes are expressed equally because both alleles are dominant. An example is a tortoise shell cat. Tortoise shell cats have both black and orange fur because they have both a dominant black allele and a dominant orange allele for coat color. The black fur is expressed by the allele for black fur and the orange fur is expressed by the allele for orange fur.

Answer 4

Dominant alleles are always expressed in the phenotype when present, masking the expression of recessive alleles. Recessive alleles are only expressed in the phenotype when two copies are present. This results in a wide range of phenotypic variations depending on the combination of alleles present in an individual.