northeast Kansas there is a creature know as a wildcat. It comes in three
colors, blue, red, and purple. This trait is controlled by a single locus
gene with incomplete dominance. A homozygous
(BB) individual is blue, a homozygous (bb) individual is red, and a heterozygous
(Bb) individual is purple. What would be the genotypes
of the offspring if a blue wildcat were crossed with a red one?
What are the genotypic and phenotypic ratios of the F2generation?
Genotypic ratio (BB:Bb:bb):
Phenotypic ratio (Blue:Purple:Red):
lubber grasshopper is a very large grasshopper, and is black with red and
yellow stripes. Assume that red stripes are expressed from the homozygous
RR genotype, yellow stripes from the homozygous
rr genotype, and both from the heterozygous
genotype. What will be the phenotypic ratio
of the F1 generation resulting from
a cross of two grasshoppers, both with red and yellow stripes (red : both
What would be the genotypic ratio
of the F1 generation (RR : Rr : rr)?
What genotypes would be produced
by crossing a grasshopper with both color stripes and one with yellow stripes
(choose all that apply)?
What phenotypes would be
produced by crossing a grasshopper with both color stripes and one with
yellow stripes (choose all that apply)?
you have two rose plants, both with pink flowers. You cross the two plants
and are surprised to find that, while most of the offspring are pink, some
are red and some are white. You decide that you like the red flowers and
would like to make more. What cross would you perform to produce the most
red flowered plants?
Your mother decides she would like some of the pink flowered
roses. Which cross would give you the most pink flowered plants?
naturalist visiting an island in the middle of a large lake observes a
species of small bird with three distinct types of beaks. Those with short,
crushing beaks (BB) consume hard shelled nuts, those with long, delicate
beaks (bb) pick the seeds from pine cones, and those with intermediate
beaks (Bb), consume both types of seeds though they are not as good at
either. Assume that this difference in beak morphology is the result of
incomplete dominance in a single locus gene.
Which of the mated pairs below will have the best adapted offspring in
a year in which most of the food available is in the form of hard shelled
What would be the phenotypic
ratio of the
F1 generation resulting
from a cross of Bb x bb (Short:Intermediate:Long)?
How many offspring of an intermediate x short beak cross
will have long beaks (assume 4)?
have rings around their tails and a habit of washing their food in water
before eating it. Suppose that both of these traits are controlled via
incomplete dominance so that wide bands on the tail are BB, medium sized
bands are Bb, and narrow bands are bb and that washing all their food is
WW, washing some of their food is Ww, and washing no food is ww. How many
of each genotype will be in the F1 generation
resulting from a cross of two racoons, both with medium sized tail bands
and that wash some of their food (assume 16)?
How many of the F1 generation
will have wide tail bands and won't wash any of their food?
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