Final answer:
A flower can display incomplete dominance, as seen with the pink snapdragons resulting from a cross between red and white homozygous parents, creating a pink, intermediate phenotype in the heterozygous offspring.
Step-by-step explanation:
Incomplete Dominance in Snapdragon Flowers
When discussing hereditary patterns, incomplete dominance is a key concept, particularly illustrated by the coloration of snapdragon flowers. In the case of snapdragons, a cross between red (CRCR) and white (CWCW) homozygous plants results in offspring with pink flowers (CRCW). This occurs because the red allele (CR) and the white allele (CW) do not demonstrate a traditional dominant-recessive relationship. Instead, both alleles contribute to the flower's phenotype, resulting in a blending of the two parent colors.
For instance, a plant that is homozygous for the red allele (RR) will display red flowers, while a homozygous white plant (WW) will have white flowers. However, a heterozygous plant (RW), possessing one allele for red and one for white, will present with pink flowers. This pink hue is due to the presence of both alleles' effects: the red allele's pigment is not completely dominant over the white allele, leading to a diluted red color appearing as pink.
When exploring this genetic concept further, we can employ a Punnett square to predict offspring phenotypes. If we cross two pink snapdragons (RW), the potential offspring could be red (RR), pink (RW), or white (WW). The resulting ratio – 1:2:1 for red, pink, and white flowers respectively – is indicative of incomplete dominance since neither allele totally overshadows the other in the heterozygote. The color obtained—pink—remains intermediate between the two parents, not a mix of distinct colors but a middle-ground phenotype.