In a species of birds, blue feathers (B) are incompletely dominant to the gene for white feathers (b). Individuals that are heterozygous (Bb) have blue-tipped feathers. A bird with blue-tipped feathers is crossed with a white bird. What is the chance that the offspring will have blue feathers

0

Explanation:

The chance that the offspring will have blue feather is 0.

From the illustration, blue feather with allele B exhibit incomplete dominance over white feather with allele b to give a blue-tipped feather phenotype.

Blue-tipped feathers bird will have the genotype Bb.

White feather bird will have the genotype bb.

Crossing both Bb and bb:

Bb   x   bb = Bb, Bb, bb, bb

Offspring

2 Bb - blue-tipped feather

2 bb - white feather

None of the offspring will have a blue feather. Hence the chance of the offspring having blue feathers is zero.

c. heat from the poles back down towards the equator.