Final answer:
The observed phenotypic ratios of the F₂ generation closely approximate the Mendelian 9:3:3:1 ratio, supporting independent assortment of alleles. Smaller sample sizes and environmental factors could introduce experimental error and affect this outcome. Different observed ratios suggest additional genetic interactions such as gene linkage or epistasis.
Step-by-step explanation:
When examining the results from the observed plant phenotypes of the F₂ generation - 2706 tall/inflated, 930 tall/constricted, 888 dwarf/inflated, and 300 dwarf/constricted - you first need to reduce these numbers to a simpler ratio. This is done by dividing each number by the smallest number of plants observed, which is 300 in this case. You get ratios of 9.02 (tall/inflated), 3.1 (tall/constricted), 2.96 (dwarf/inflated), and 1 (dwarf/constricted). These numbers closely approximate the expected Mendelian 9:3:3:1 ratio, which supports the idea that alleles segregate independently into gametes according to Mendelian genetics.
If the experiment was conducted with far fewer plants, the ratio might not be as close to the expected 9:3:3:1 due to the effects of random chance affecting smaller sample sizes. This inconsistency would make it harder to form a clear conclusion about the genetic ratios at play. Additionally, environmental factors such as a windy day might introduce experimental error, such as losing some plants or mixing them, further distorting the ratios.
The expected ratio of phenotypes from a dihybrid cross is typically 9:3:3:1, reflecting the independent assortment of two gene pairs. If a different ratio was observed, like in the shepherd's purse plant, it can indicate other genetic interactions are at play, such as gene linkage or epistasis, influencing the phenotypic outcome. Therefore, the observed phenotypic ratios from a dihybrid cross can tell us a lot about the genetic mechanisms behind trait inheritance.