What is a gene?

A gene is defined as a piece of DNA that codes for a specific trait. Genes serve as the basic unit of heredity and are responsible for carrying the information that directs the development, functioning, growth, and reproduction of all living organisms. Each gene has a particular sequence of nucleotides that determines the characteristics of the organism by encoding specific proteins, which ultimately influence physical traits and functions.

The focus on genes as specific sequences that correspond to particular traits underscores their role in biology. This clear delineation between the structural aspect of DNA and the functional aspect of genetic expression is foundational in genetics, making this definition particularly accurate.