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Correct Answer: 100% round seeded.
the correct answer to the question is "100% round seeded." this outcome is based on the principles of mendelian genetics, specifically the law of dominance, which states that in a heterozygote, one trait will conceal the presence of another trait for the same characteristic. here is a detailed explanation:
in pea plants, the trait for seed shape has two alleles: the dominant round-seed allele (r) and the recessive wrinkle-seed allele (r). a dominant allele, when present, will always express itself, masking the effect of a recessive allele. therefore, a plant with at least one dominant allele (r) will have round seeds.
in this scenario, the parents are described as homozygous—one parent is homozygous dominant (rr), and the other is homozygous recessive (rr). homozygous means that both alleles for the trait are the same in the individual. hence, the homozygous dominant parent has two dominant alleles (rr) and will always produce gametes (reproductive cells) carrying the dominant allele (r). similarly, the homozygous recessive parent has two recessive alleles (rr) and will always produce gametes carrying the recessive allele (r).
when these two parents are crossed (rr x rr), each gamete from the homozygous dominant parent (r) will fuse with a gamete from the homozygous recessive parent (r) during fertilization. the resulting offspring will thus all have the genotype rr - one allele being dominant (r) and the other recessive (r). given the dominance of the r allele, all these offspring will express the dominant trait, resulting in round seeds.
therefore, all the offspring in this cross will be heterozygous (rr) with round seeds, leading to the answer of "100% round seeded." all offspring are genetically identical in terms of this trait, and no offspring will have wrinkle seeds, as the presence of the dominant allele (r) in each heterozygous (rr) offspring masks the effect of the recessive allele (r).
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