What are alleles?

Alleles are defined as specific versions of a gene. Each gene can have multiple forms, which are the alleles, resulting from variations in the DNA sequence. For example, a gene that determines flower color in a plant may have a blue allele and a red allele. These different alleles can influence the traits expressed by the organism, contributing to genetic diversity.

Understanding alleles also requires recognizing their role in heritable traits, where an individual inherits one allele from each parent, leading to different combinations that manifest as different phenotypes. In genetics, discussing alleles is foundational because it lays the groundwork for understanding inheritance patterns, including concepts like dominance, recessiveness, and co-dominance.

The other potential choices describe concepts related to genetics but do not precisely define what alleles are. Different forms of a phenotype refer to observable characteristics rather than the underlying genetic variations. Types of chromosomes refer to the structural components of genetic material in cells, and mutations specifically refer to alterations in DNA sequences that can create new alleles but are not themselves the alleles. Thus, the definition of alleles as specific versions of a gene is the most accurate understanding in this context.