Genes are molecular units of heredity. Genes are like the recipe for a person. The types of genes a person has in their DNA determine their traits. Genes influence eye color, hair color, height, and just about every physical characteristic of a person.
When parents pass their genetic traits to their offspring, it is called heredity. All of the genes that a person has they inherited from their parents.
This chart displays different possible eye colors that are determined by genes.