GENETIC PROBLEMS:
1.
In a certain species of dog, a black nose (B) is dominant over a pink nose (b). Predict the
genotypes and phenotypes produced by crossing a pink-nosed male dog and a female with a
heterozygous wet nose.
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2.
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Using the information from above, cross two dogs that areheterozygous for pink nose.
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3.
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A purebred round pea plant is crossed with a purebred wrinkled pea plant. Round is dominant.
What are the possible genotypes and phenotypes of the resulting offspring plants?
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4.
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A couple that can both ro11 their tongues are heterozygous for the trait and they have a child.
Rolling tongue is dominant to not rolling tongue. What is the probability of having a child that
can roll their tongue? Cannot role their tongue?
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Tungue
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5.
Poinsettias are available in three colors because they demonsfiate incomplete dominance. This
beautiful flower can be red (R), white (W), or a unique heterozygous plant. Set up a Punnett
Square that demonstrates the cross b:y""* each of the following combinations:
a.
red (RR) x white (WW)
List the possible genotypes-& describe the phenotypes from the cross?
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b. A white plant crosses with aheterczygous poinsettia plant.
What are the possible genotypes & phenotypes from the cross?
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