5. The F2 generation of a cross between a parental tall and a parental short pea plant is 298 tall plants and 102 short plants. What do these results say about the genes for stem height in the pea plant?

The answer is XX.

Explanation:

Let us say that X is the dominant gene and x is the recessive gene for the height of the pea plants. Pea plants need to be homozygous or heterozygous  to have the short phenotype which means it needs to have the genotype xx or Xx.

The F2 offspring has a ratio of 74,5% tall plants and 25,5% short plants. For these results, the stem height pea plant needs to be homozygous which is an XX genotype for the tall pea plant.

I hope this answer helps.