Genetic problems

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Genetic problems

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Question #1

How many different kinds of gametes could the following individuals produce?

1. aaBb

2. CCDdee

3. AABbCcDD

4. MmNnOoPpQq

5. UUVVWWXXYYZz

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Question #1

Remember the formula 2n

Where n = # of heterozygous

1. aaBb = 2

2. CCDdee = 2

3. AABbCcDD = 4

4. MmNnOoPpQq = 32

5. UUVVWWXXYYZz = 2

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Question #2

In dogs, wire-haired is due to a dominant gene (W), smooth-haired is due to its recessive allele (w).

WW, Ww = wire haired

ww = smooth haired

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Question #2A

If a homozygous wire-haired dog is mated with a smooth-haired dog, what type of offspring could be produced.

W W

w

w

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Question #2A

W W

w Ww Ww

fg F1 generation

w Ww Ww all heterozygous

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Question #2B

What type(s) of offspring could be produced in the F2 generation?

Must breed the F1 generation to get the F2.

Results of F1 Cross: Ww x Ww

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Question #2B

W w

W WW Ww F2 generation

w Ww ww

genotype: 1:2:1 ratio

phenotype: 3:1 ratio

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Question #2C

Two wire-haired dogs are mated. Among the offspring of their first litter is a smooth-haired pup.

If these, two wire-haired dogs mate again, what are the chances that they will produce another smooth-haired pup?

What are the chances that the pup will wire-haired pup?

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Question #2C

W w

W WW Ww F2 generation

w Ww ww

- 1/4 or 25% chance for smooth-haired

- 3/4 or 75% chance for wire-haired

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Question #2D

A wire-haired male is mated with a smooth-haired female. The mother of the wire-haired male was smooth-haired.

What are the phenotypes and genotypes of the pups they could produce?

Show the results of crossing: Ww x ww

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