The gene that shows is called a what? ? i need a word

The genes are responsible for the determination of the traits in the organism, which is observable and referred as a phenotype.

The genes are the functional unit of the genetic material. A single gene in a organism is composed of two alleles, these two allele together are referred as the genotype of the organism.

Every gen code for an observable character, which affected the genotype of the organism. This observable character of the organism is referred as the phenotype.