Pieces of DNA that occupy specific locations on chromosomes and that control different activities and details of a person's makeup and function (e.g., eye color, production of certain enzymes, etc.).
Basic units of hereditary characteristics passed on through reproduction (part of chromosomes).
The hereditary material coded in cells that determine how an organism will look and behave. A gene is a single unit located on a chromosome and is thereby passed from one generation to the next. Genes are what makes each species and individual unique. For example, genes are responsible for hair colour and texture in humans.