NONDOMINANCE OR INCOMPLETE DOMINANCE

1 In chickens BB calls for a black chicken. WW calls for a white chicken, The BW combination calls for the

blue Andalusian chicken. Cross a blue hen with a blue rooster. 2 A black chicken is mated with an Andalusian blue chicken. What types of offspring might be expected? 3 In chickens, rose comb (R) is dominant to single comb (r). What type of offspring would be expected from a

white rooster who is heterozygous rose-combed who is crossed with a single-combed Andalusian blue hen? 4 In four o’clocks, flower color is due to nondominance. Some flowers are red, some are white, and others are

pink. Cross a red flower with a pink flower. a) What is the genotype of the red flower? b) What is the genotype of the pink flower? c) What is the probability of getting red offspring? d) What is the probability of getting white offspring? e) What is the probability of getting pink offspring? 5 In cattle, the RR calls for a red cow; the WW for a white cow; and the RW calls for roan color. A red bull

and a white cow are mated. What type of offspring would be expected? Give the genotypes and phenotypes and their probabilities.

6 A cattle breeder knows that the hornless condition (H) is dominant over horned (h). He mates a

heterozygous hornless cow who is roan colored with a horned roan bull. What type of offspring would be expected from this cross? Give the probability of each.

7 The shape and color of radishes are controlled by two independent pairs of genes that show no dominance.

The color may be red (RR), white (WW), or purple (RW). What type of offspring might be expected when purple radishes are mated with white radishes?

8 The shape and color of radishes are controlled by two independent pairs of genes that show no dominance.

The color may be red (RR), white (WW), or purple (RW). The shape may be long (LL), round (OO), or oval (LO). Show a cross between a long, red radish and a round, white radish. Show the genotypes, the phenotypes and the probabilities of the first generation. If the offspring of the F1 generation are allowed to self-pollinate, what types of offspring will be expected in the F2 generation?

9 In some cats, the gene for tail length shows incomplete dominance. When a cat with a long tail is bred to a

cat with no tail, the resulting offspring have short tails. For each of the following, predict the types of offspring that would result: a) A long tail cat bred to a cat with no tail b) A long tail cat bred to a short tail cat c) Two short tail cats

10 In a particular plant, long stem is dominant over short stem. This same plant may produce red flowers or

white flowers with this trait showing nondominance. Cross a heterozygous, long stemmed pink plant with a heterozygous long stemmed, red flowering plant.

 

Name __________________________

NONDOMINANCE OR INCOMPLETE DOMINANCE

1 In chickens BB calls for a black chicken. WW calls for a white chicken. The BW combination calls for the

blue Andalusian chicken. Cross a blue hen with a blue rooster. 2 A black chicken is mated with an Andalusian blue chicken. What types of offspring might be expected? 3 In chickens, rose comb (R) is dominant to single comb (r). What type of offspring would be expected from a

white rooster who is heterozygous rose-combed who is crossed with a single-combed Andalusian blue hen? ____________ What is the genotype of the heterozygous rose combed white chicken? ____________ What is the genotype of the single combed blue chicken?

 

4 In four o’clocks, flower color is due to nondominance. Some flowers are red, some are white, and others are

pink. Cross a red flower with a pink flower.

_____ What is the genotype of the red flower?

_____ What is the genotype of the pink flower?

_____ What is the probability of getting red offspring?

_____ What is the probability of getting white offspring?

_____ What is the probability of getting pink offspring?

5 In cattle, the RR calls for a red cow; the WW for a white cow; and the RW calls for roan color. A red bull

and a white cow are mated. What type of offspring would be expected? Give the genotypes and phenotypes and their probabilities.

6 A cattle breeder knows that the hornless condition (H) is dominant over horned (h). He mates a

heterozygous hornless cow who is roan colored with a horned roan bull. What type of offspring would be expected from this cross? Give the probability of each.

__________ Genotype of the heterozygous hornless roan? __________ Genotype of the horned roan?

 

7 The shape and color of radishes are controlled by two independent pairs of genes that show no dominance.

The color may be red (RR), white (WW), or purple (RW). What type of offspring might be expected when purple radishes are mated with white radishes?

8 The shape and color of radishes are controlled by two independent pairs of genes that show no dominance.

The color may be red (RR), white (WW), or purple (RW). The shape may be long (LL), round (OO), or oval (LO). Show a cross between a long, red radish and a round, white radish. Show the genotypes, the phenotypes and the probabilities of the first generation.

___________ Genotype of the long, red radish ___________ Genotype of the round, white radish. ___________ What will be the genotype of all the offspring? ___________ What will be the phenotype of all the offspring? If the offspring of the F1 generation are allowed to self-pollinate, what types of offspring will be expected in

the F2 generation?

 

9 In some cats, the gene for tail length shows incomplete dominance. When a cat with a long tail is bred to a cat with no tail, the resulting offspring have short tails. For each of the following, predict the types of offspring that would result:

a) A long tail cat bred to a cat with no tail:

b) A long tail cat bred to a short tail cat:

c) Two short tail cats:

10 In a particular plant, long stem is dominant over short stem. This same plant may produce red flowers or

white flowers with this trait showing nondominance. Cross a heterozygous long stemmed pink plant with a heterozygous long stemmed red flowering plant.

_______ Genotype of the heterozygous long-stemmed pink _______ Genotype of the heterozygous long-stemmed red