An increase in genetic variation
INCOMPLETE DOMINANCE INHERITANCE:
<span>5. In Andalusian fowl, B is the gene for black plumage (head feathers) and B' (pronounced "B prime") is the gene for white plumage. These genes, however, show incomplete dominance. The heterozygous (BB') condition results in blue plumage. List the genotypic and phenotypic ratios expected from the following crosses: a) black x blue b) blue x blue c) blue x white</span>
<span>6. </span><span>In snapdragons, petal color is determined by a single gene locus with two alleles making the "red" allele (R) incompletely dominant to the "white" allele (r). Heterozygotes have petals, which are neither red nor white, but pink. a) If a true-breeding red flower is pollinated with pollen from a white flower: What fraction of the seeds (F1 generation) would be expected to produce red-flowered plants? What fraction of the gametes produced by the F1 plants would be expected to bear the R allele? b) If two pink flowered plants are crossed, what genotypic and phenotypic ratios are expected among the offspring (F1 generation)?</span>
The respiratory system contains the lungs, so the answer is C. Hope this helps.
