Final answer:
When two genes are tightly linked with no crossing over, their alleles will always be inherited together, resulting in no recombinant gametes. This leads to a deviation from the classic Mendelian prediction of a dihybrid cross. As the distance between two linked genes increases, the probability of crossovers between them also increases.
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 referred to as gene linkage. If two genes are tightly linked with no crossing over, it means that the alleles for these genes will always be inherited together, resulting in no recombinant gametes.
This leads to a deviation from the classic Mendelian prediction of a 9:3:3:1 outcome in a dihybrid cross. As the distance between two linked genes increases, the probability of crossovers between them also increases, and they behave more like they are on separate chromosomes.