Final answer:
Seed purity refers to the percentage of the desired crop seed in a seed lot, not weed/other crop seeds or inert matter. The correct expectation for F1 offspring from true-breeding plants with green and yellow seeds would be 100% yellow seeds, as yellow is the dominant trait.
Step-by-step explanation:
The statement that seed purity is the percentage of weed/other crop seeds or inert matter that is in a seed lot is false. Seed purity actually refers to the percentage of the desired crop seed in a seed lot, so it represents the opposite of what the question suggests. High seed purity means that a high percentage of the seeds in the lot are the desired type without significant contamination from weeds, other crops, or inert matter. Students performing a cross involving seed color in garden pea plants can expect certain outcomes in the F1 offspring. When cross-breeding true-breeding plants with yellow seeds (dominant trait) and green seeds (recessive trait), the F1 offspring would be expected to have 100 percent yellow seeds, since the yellow trait is dominant. This means that all the F1 offspring would display the dominant yellow seed color.