In gorillas, the alleles for silver-gray fur (G) and yellow eyes (E) are dominant over the alleles for black fur (g) and blue eyes (e). Assume that these genes are unlinked.
a). If a gorilla names George was the product of a homozygous dominant father and a homozygous recessive mother, what are the genotype and phenotype of George's parents?
b). what are George's genotype and phenotype?
c). If the George is mated to Gigi, a gorilla who has exactly the same genotype as himself what would be the expected phenotypic ration of their offspring?
I will be happy to critique your thinking.
a) To determine the genotype and phenotype of George's parents, we need to understand the inheritance of the fur color (Gg or GG) and eye color (Ee or EE) alleles.
Since George is homozygous dominant for both traits (GGEE), we know that his mother must be homozygous recessive for both traits (ggee). This is because George inherited one allele for fur color and one allele for eye color from each of his parents.
Therefore, George's father must be homozygous dominant for both traits (GGEE). This is because George inherited the dominant alleles for both traits from his father, and the dominant alleles mask the presence of the recessive alleles.
The genotype of George's parents:
- Father: GGEE
- Mother: ggee
The phenotype of George's parents:
- Father: Silver-gray fur and yellow eyes
- Mother: Black fur and blue eyes
b) George's genotype is GGEE, which means he is homozygous dominant for both traits.
George's phenotype is silver-gray fur and yellow eyes. This is because the dominant alleles (G and E) for fur color and eye color, respectively, determine these phenotypes.
c) When George, who is GGEE, mates with Gigi, who also has the exact same genotype (GGEE), we can determine the expected phenotypic ratio of their offspring using Punnett squares.
The possible genotypes of their offspring are:
- GGEE (silver-gray fur and yellow eyes)
- GGEE (silver-gray fur and yellow eyes)
Since both genotypes result in the same phenotype, the expected phenotypic ratio of their offspring would be 100% silver-gray fur and yellow eyes.