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Correct Answer: incomplete dominance.
the question discusses a scenario where a red flower and a white flower are crossed, resulting in a pink flower. this outcome is a classic example of incomplete dominance. incomplete dominance occurs when the phenotype of the heterozygous genotype is an intermediate of the phenotypes of the homozygous genotypes. in this case, neither the red nor the white color is completely dominant, so the resulting offspring (pink flower) shows a mix of both parental traits.
to understand this concept further, consider the genetic makeup of the flowers. let's denote the allele for red color as 'r' and the allele for white color as 'w'. in a scenario of complete dominance, one of these alleles would be dominant over the other, completely masking the effect of the recessive allele in the phenotype of the heterozygous genotype. however, in incomplete dominance, neither allele is completely dominant. therefore, when a red flower (rr) is crossed with a white flower (ww), the offspring will have the genotype rw. this rw genotype expresses a phenotype that is an intermediate of both parents, which is the pink color.
this example of incomplete dominance is important in the study of genetics because it demonstrates how genetic traits can blend, rather than showing an all-or-nothing expression (as seen in complete dominance). it highlights the complexity of genetic inheritance and the variety of possible outcomes beyond the classical mendelian genetics.
the other options listed—polyploidy, independent assortment, and homozygosity—do not correctly describe the genetic situation presented. polyploidy involves organisms having more than two complete sets of chromosomes, which is not indicated in the question. independent assortment refers to the random distribution of different pairs of alleles to gametes, which is not specifically relevant to the color blending seen here. homozygosity refers to having identical alleles at a gene locus, which also does not apply as the pink flower is heterozygous.
therefore, the correct answer is incomplete dominance, as it best explains the genetic interaction leading to the pink flower phenotype in the offspring of red and white flower parents.
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