homòlegs

Homòlegs is a term used in various scientific fields to describe entities that share a common origin or structural similarity. In genetics, homòlegs refer to genes or chromosomes that are similar due to their shared ancestry. Homologous chromosomes, for example, are pairs of chromosomes in a diploid organism that contain the same genes in the same order, one inherited from each parent. Similarly, homologous genes, or paralogs, are genes within the same species that arose from gene duplication.

In organic chemistry, homòlegs are members of a homologous series, which is a sequence of compounds with the same general formula, usually varying by a single parameter such as the length of a carbon chain. For instance, alkanes like methane, ethane, and propane form a homologous series, differing by a –CH2– group. This structural similarity leads to predictable trends in their physical and chemical properties.

The concept of homòlegs is crucial for understanding evolutionary relationships, gene function, and chemical reactivity. By identifying homòlegs, scientists can infer the function of unknown genes based on the known function of their counterparts, or predict the properties of new chemical compounds based on the behavior of similar substances. This comparative approach is fundamental to many areas of scientific research.