What is defined as an inherited factor that contributes to a characteristic?

A gene is defined as an inherited factor that contributes to a characteristic. Genes are segments of DNA that code for proteins, which play key roles in determining traits and characteristics in living organisms. Each gene can influence specific traits, such as eye color, height, or susceptibility to certain diseases.

In contrast, the term heterozygote refers to an individual having two different alleles of a gene, which is relevant to genetic variation but does not itself define an inherited factor. The term locus refers to the specific physical location of a gene on a chromosome, rather than the gene itself. Phenotype describes the observable characteristics or traits of an organism, which result from the interaction of its genotype (the genetic constitution) and the environment, but is not the inherited factor itself. Thus, the correct identification of a gene as the inherited factor aligns perfectly with its role in genetics.