When it comes to genetic traits, they are determined by the genes an individual inherits from their parents. Each person inherits one gene for each trait from their mother and one gene for the same trait from their father. These genes can be the same (homozygous) or different (heterozygous) for a particular trait.
For example, in the case of a genetic trait like eye color, if someone has one gene for brown eyes from one parent and one gene for blue eyes from the other parent, they would be considered heterozygous for that trait. If both genes are the same, such as two genes for brown eyes, they would be homozygous for that trait.
It's essential to understand that different genes can result in various genetic traits, and genetics is a complex field that involves the interplay of many genes for different traits. The specific genetic trait a person exhibits depends on the combination of genes they inherit from their parents. If you have a specific question or need more information on a particular aspect of genetics, please provide more details, and I'd be happy to help further.