* Genotype: The actual genetic makeup of an organism (like Gg or GG).
* Phenotype: The observable physical or biochemical characteristics of an organism (like eye color, height, or disease susceptibility).
The reason a Gg organism can have the same phenotype as a GG organism is due to the concept of dominant and recessive alleles.
* Dominant Allele: An allele that expresses its trait even when paired with a different (recessive) allele.
* Recessive Allele: An allele that only expresses its trait when paired with another identical recessive allele.
In your example, let's say the "G" allele represents a gene for brown eyes, and the "g" allele represents a gene for blue eyes.
* GG: This individual has two copies of the dominant brown eye allele. They will have brown eyes.
* Gg: This individual has one dominant brown eye allele and one recessive blue eye allele. Since brown is dominant, this individual will also have brown eyes.
* gg: This individual has two copies of the recessive blue eye allele. They will have blue eyes.
In summary: A Gg individual can have the same phenotype as a GG individual because the dominant allele (G) masks the expression of the recessive allele (g).
