Final answer:
When two genes are located in close proximity on the same chromosome, their alleles tend to be transmitted together through meiosis. Geneticists have used the proportion of recombinant gametes as a measure of how far apart genes are on a chromosome, constructing linkage maps that show the locations of genes.
Step-by-step explanation:
When two genes are located in close proximity on the same chromosome, their alleles tend to be transmitted together through meiosis. This is known as linkage. If the genes are close together on the chromosome, they are likely to be inherited together.
However, they may be separated by crossing-over during meiosis, which can result in independent inheritance. Geneticists have used the proportion of recombinant gametes as a measure of how far apart genes are on a chromosome, constructing linkage maps that show the locations of genes.