What is an allele’s role in determining traits?

An allele is indeed an alternative form of a gene, which means it can vary in its sequence or structure. These variations influence the specific traits expressed in an organism. Each individual typically has two alleles for each gene - one inherited from each parent. The combination of these alleles can determine dominant and recessive traits, leading to different phenotypes. For example, in pea plants, the allele for tall plants can be dominant over the allele for short plants. Hence, an organism's traits, such as height, color, or shape, can be directly affected by the specific alleles it possesses. This diverse range of alleles contributes to the genetic variation seen within a population and influences how traits are inherited across generations.