An allele is one of the possible forms of a gene that can be found at a specific position on a chromosome. Genes determine the characteristics, traits, and functions of an organism, and each gene has two alleles, one inherited from each parent. Alleles can be either dominant or recessive, where a dominant allele is expressed and masks the presence of a recessive allele. The combination of alleles determines the genotype of an individual, which in turn influences their phenotype or observable traits.
