Final answer:
Centi-morgans (cM) are units of genetic recombination used to measure the likelihood that alleles will be separated during meiosis based on the frequency of recombination. They help in creating genetic maps by showing the order and relative distances between genes on a chromosome.
Step-by-step explanation:
Centi-morgans (cM) are units of genetic recombination. These map units are named after geneticist Thomas Hunt Morgan, and they measure the genetic distance between points on a chromosome, which is indicative of the frequency of recombination between them during meiosis. One centimorgan corresponds to a recombination frequency of 0.01, which means there is a 1% chance that a crossover will occur between two genes during meiosis. This unit reflects the likelihood that two alleles will become separated during the crossing over of homologous chromosomes, which can then result in new combinations of alleles in the offspring.
An example of how centimorgans are used can be found when considering genes on a chromosome. If the recombination frequency between two genes is calculated to be 0.05, this means that there is a 5% chance of recombination occurring between these genes, which equates to 5 cM. This measure helps in creating genetic maps that establish the order and relative distances of genes on a chromosome.