Which term refers to a section of DNA that controls a trait?

The term that refers to a section of DNA that controls a trait is a gene. Genes are specific sequences of nucleotides within the DNA that carry the instructions for making proteins, which ultimately determine an organism's traits or characteristics. Each gene can be associated with a particular function or feature, such as eye color or flower shape in plants.

Chromosomes contain many genes, serving as the structures that organize and package DNA within the cell. Alleles are different forms of a gene that can exist and may lead to variations in traits. The genome, on the other hand, refers to the complete set of genetic material in an organism, encompassing all of its genes and non-coding sequences. Understanding the role of genes in heredity and variation is fundamental in genetics and biodiversity studies.