allelom

Allelom is a term used in biology to describe the phenomenon where one allele can mask the expression of another allele at the same gene locus. This interaction is known as dominance. When an organism has two different alleles for a particular gene, one allele, the dominant allele, will determine the phenotype, while the other allele, the recessive allele, will have its effect hidden. The recessive allele is only expressed when an individual inherits two copies of it.

The concept of allelism is fundamental to understanding Mendelian inheritance. Gregor Mendel's experiments with pea plants demonstrated these principles. For example, if a pea plant has one allele for purple flowers and one allele for white flowers, and the allele for purple flowers is dominant, then the plant will have purple flowers. The allele for white flowers is recessive and its expression is masked by the dominant purple allele.

Not all allelic interactions are simple dominant-recessive relationships. Incomplete dominance occurs when neither allele is completely dominant, resulting in a blended phenotype. Codominance is another type, where both alleles are expressed simultaneously. Understanding allelism is crucial for predicting inheritance patterns and understanding genetic variation within populations. It explains why individuals with the same genes can exhibit different traits.