Chapter 5

Question 1

The R locus determines flower color in a new plant species. Plants that are genotype RR have red flowers, and plants that are rr have white flowers. However, Rr plants have pink flowers. What type of inheritance does this demonstrate for flower color in these plants?

a. Complete dominance
b. Incomplete dominance
c. Codominance
d. Complementation
e. Lethal alleles

Answer 1

b. Incomplete dominance

Question 2

Interactions among the human ABO blood group alleles involve _______ and ________.

a. co-dominance; complete dominance
b. codominance; incomplete dominance
c. complete dominance; incomplete dominance
d. epistasis; complementation
e. continuous variation; environmental variation

Answer 2

a. co-dominance; complete dominance

Question 3

In the endangered African watchamakallit, the offspring of a true-breeding black parent and a true-breeding white parent are all gray. When the gray offspring are crossed among themselves, their offspring occur in a ratio of 1 black:2 gray:1 white. Upon close examination of the coats, each hair of a gray animal is gray. What is the mode of inheritance?

a. One gene pair with black dominant to white
b. One gene pair with codominance
c. One gene pair with incomplete dominance
d. Two gene pairs with recessive epistasis
e. Two gene pairs with duplicate genes

Answer 3

c. One gene pair with incomplete dominance

Question 4

Suppose that extra fingers and toes are caused by a recessive trait, but it appears in only 60% of homozygous recessive individuals. Two heterozygotes conceive a child. What is the probability that this child will have extra fingers and toes?

a. 0.05
b. 0.10
c. 0.15
d. 0.25
e. 0.33

Answer 4

c. 0.15

Question 5

Polydactyly is the condition of having extra fingers or toes. Some polydactylous persons possess extra fingers or toes that are fully functional, whereas others possess only a small tag of extra skin. This is an example of

a. variable expressivity.
b. complete dominance.
c. independent assortment.
d. complementation.
e. cytoplasmic inheritance.

Answer 5

a. variable expressivity.

Question 6

Achondroplasia is a common cause of dwarfism in humans. All individuals with achondroplasia are thought to be heterozygous at the locus that controls this trait. When two individuals with achondroplasia mate, the offspring occur in a ratio of 2 achondroplasia:1 normal. What is the most likely explanation for these observations?

a. Achondroplasia is incompletely dominant to the normal condition.
b. Achondroplasia is codominant to the normal condition.
c. The allele that causes achondroplasia is a dominant lethal allele.
d. The allele that causes achondroplasia is a recessive lethal allele.
e. The allele that causes achondroplasia is a late-onset lethal allele.

Answer 6

d. The allele that causes achondroplasia is a recessive lethal allele.

Question 7

Crossing two yellow mice results in 2/3 yellow offspring and 1/3 nonyellow offspring. What percentage of offspring would you expect to be nonyellow if you crossed two nonyellow mice?

a. 25%
b. 33%
c. 66%
d. 75%
e. 100%

Answer 7

e. 100%

Question 8

In humans, blood types A and B are codominant to each other and each is dominant to O. What blood types are possible among the offspring of a couple of blood types AB and A?

a. A, B, AB, and O
b. A, B, and AB only
c. A and B only
d. A, B, and O only
e. A and AB only

Answer 8

b. A, B, and AB only

Question 9

A mother of blood type A gives birth to a child with blood type O. Which of the following could NOT be the blood type of the father?

a. A
b. B
c. O
d. AB
e. Any of the above is a possible blood type of the father.

Answer 9

d. AB

Question 10

You are studying body color in an African spider and have found that it is controlled by a single gene with four alleles: B (brown), br (red), bg (green), and by (yellow). B is dominant to all the other alleles, and by is recessive to all the other alleles. The bg allele is dominant to by but recessive to br. You cross a pure-breeding brown spider with a pure-breeding green spider. Predict the genotype of the progeny.

a. B/bg
b. Br/bg
c. br/by
d. by/bg
e. B/by

Answer 10

a. B/bg

Question 11

You are studying body color in an African spider and have found that it is controlled by a single gene with four alleles: B (brown), br (red), bg (green), and by (yellow). B is dominant to all the other alleles, and by is recessive to all the other alleles. The bg allele is dominant to by but recessive to br. You cross a pure-breeding brown spider with a pure-breeding green spider. Predict the phenotype of the progeny.

a. Half brown, half green
b. Three-fourths brown, one-fourth green
c. All brown
d. All green
e. All yellow

Answer 11

c. All brown

Question 12

In rabbits, an allelic series helps to determine coat color: C (full color), cch (chinchilla; gray color), ch (Himalayan; white with black extremities), and c (albino; all white). The C allele is dominant to all others, cch is dominant to ch and c, ch is dominant to c, and c is recessive to all the other alleles. This dominance hierarchy can be summarized as C > cch > ch > c. Indicate the phenotypic ratios expected if rabbits with the cross Ccch Cch.

a. 1 full color:1 chinchilla
b. 1 full color:1 Himalayan
c. 1 chinchilla:1 Himalayan
d. 3 full color:1 chinchilla
e. 2 full color:1 Himalayan:1 albino

Answer 12

d. 3 full color:1 chinchilla

Question 13

In rabbits, an allelic series helps to determine coat color: C (full color), cch (chinchilla; gray color), ch (Himalayan; white with black extremities), and c (albino; all white). The C allele is dominant to all others, cch is dominant to ch and c, ch is dominant to c, and c is recessive to all the other alleles. This dominance hierarchy can be summarized as C > cch > ch > c. Indicate the phenotypic ratios expected if rabbits with the cross Cch chc.

a. 1 full color:1 chinchilla
b. 1 full color:1 Himalayan
c. 1 chinchilla:1 Himalayan
d. 3 full color:1 chinchilla
e. 2 full color:1 Himalayan:1 albino

Answer 13

b. 1 full color:1 Himalayan

Question 14

In rabbits, an allelic series helps to determine coat color: C (full color), cch (chinchilla; gray color), ch (Himalayan; white with black extremities), and c (albino; all white). The C allele is dominant to all others, cch is dominant to ch and c, ch is dominant to c, and c is recessive to all the other alleles. This dominance hierarchy can be summarized as C > cch > ch > c. Indicate the phenotypic ratios expected if rabbits with the cross Cch cc.

a. 1 full color:1 chinchilla
b. 1 full color:1 Himalayan
c. 1 chinchilla:1 Himalayan
d. 3 full color:1 chinchilla
e. 2 full color:1 Himalayan:1 albino

Answer 14

b. 1 full color:1 Himalayan

Question 15

In rabbits, an allelic series helps to determine coat color: C (full color), cch (chinchilla; gray color), ch (Himalayan; white with black extremities), and c (albino; all white). The C allele is dominant to all others, cch is dominant to ch and c, ch is dominant to c, and c is recessive to all the other alleles. This dominance hierarchy can be summarized as C > cch > ch > c. Indicate the phenotypic ratios expected if rabbits with the cross cchch chc.

a. 1 full color:1 chinchilla
b. 1 full color:1 Himalayan
c. 1 chinchilla:1 Himalayan
d. 3 full color:1 chinchilla
e. 2 full color:1 Himalayan:1 albino

Answer 15

c. 1 chinchilla:1 Himalayan

Question 16

In rabbits, an allelic series helps to determine coat color: C (full color), cch (chinchilla; gray color), ch (Himalayan; white with black extremities), and c (albino; all white). The C allele is dominant to all others, cch is dominant to ch and c, ch is dominant to c, and c is recessive to all the other alleles. This dominance hierarchy can be summarized as C > cch > ch > c. Indicate the phenotypic ratios expected if rabbits with the cross Cc chc.

a. 1 full color:1 chinchilla
b. 1 full color:1 Himalayan
c. 1 chinchilla:1 Himalayan
d. 3 full color:1 chinchilla
e. 2 full color:1 Himalayan:1 albino

Answer 16

e. 2 full color:1 Himalayan:1 albino

Question 17

A mother with blood type A has a child with blood type A. Give all possible blood types for the father of this child.

a. O
b. B, AB
c. A, AB
d. A, B, O
e. A, B, AB, O

Answer 17

e. A, B, AB, O

Question 18

A mother with blood type B has a child with blood type O. Give all possible blood types for the father of this child.

a. O
b. B, AB
c. A, AB
d. A, B, O
e. A, B, AB, O

Answer 18

d. A, B, O

Question 19

A mother with blood type A has a child with blood type AB. Give all possible blood types for the father of this child.

a. O
b. B, AB
c. A, AB
d. A, B, O
e. A, B, AB, O

Answer 19

b. B, AB

Question 20

A mother with blood type AB has a child with blood type B. Give all possible blood types for the father of this child.

a. O
b. B, AB
c. A, AB
d. A, B, O
e. A, B, AB, O

Answer 20

e. A, B, AB, O

Question 21

You are studying a gene that controls ossicone (horn) length in giraffes. The wild-type long-ossicone allele (L) is dominant to the mutant short-ossicone (l) allele. However the L allele is only 60% penetrant. You cross two heterozygous giraffes. What proportion of offspring would you expect to exhibit the long ossicone phenotype? Assume the penetrance of L applies equally to both homozygotes and heterozygotes.

a. 0.40
b. 0.45
c. 0.55
d. 0.60
e. 0.75

Answer 21

b. 0.45

Question 22

You are studying a gene that controls ossicone (horn) length in giraffes. The wild-type long-ossicone allele (L) is dominant to the mutant short-ossicone (l) allele. However, the L allele is only 60% penetrant. You cross two heterozygous giraffes. What proportion of offspring would you expect to exhibit the short ossicone phenotype? Assume the penetrance of L applies equally to both homozygotes and heterozygotes.

a. 0.25
b. 0.40
c. 0.45
d. 0.55
e. 0.60

Answer 22

d. 0.55

Question 23

Hair color is determined in Labrador retrievers by alleles at the B and E loci. A dominant allele B encodes black pigment, whereas a recessive allele b encodes brown pigment. Alleles at a second locus affect the deposition of the pigment in the shaft of the hair; dominant allele E allows dark pigment (black or brown) to be deposited, whereas recessive allele e prevents the deposition of dark pigment, causing the hair to be yellow. What type of gene interaction does this represent?

a. Recessive epistasis
b. Dominant epistasis
c. Duplicate recessive epistasis
d. Duplicate dominant epistasis
e. Dominant and recessive epistasis

Answer 23

a. Recessive epistasis

Question 24

Hair color is determined in Labrador retrievers by alleles at the B and E loci. A dominant allele B encodes black pigment, whereas a recessive allele b encodes brown pigment. Alleles at a second locus affect the deposition of the pigment in the shaft of the hair; dominant allele E allows dark pigment (black or brown) to be deposited, whereas recessive allele e prevents the deposition of dark pigment, causing the hair to be yellow. A black female Labrador retriever was mated with a yellow male. Half of the puppies were black and half were yellow. If the genotype of the black female parent was Bb Ee, then what was the genotype of the other parent?

a. bb ee
b. bb EE
c. Bb ee
d. BB ee
e. BB EE

Answer 24

d. BB ee

Question 25

Suppose that the “fabulous” phenotype is controlled by two genes, A and B, as shown in the diagram below. Allele A produces enough enzyme 1 to convert “plain” to “smashing.” Allele a produces no enzyme 1. Allele B produces enough enzyme 2 to convert “smashing” to “fabulous.” Allele b produces no enzyme 2. The A and B genes are both autosomal and assort independently.

What will be the phenotype(s) of the F1 offspring of a true-breeding “fabulous” father and a true-breeding “plain” mother (aa bb)?

a. All “plain”
b. All “smashing”
c. All “fabulous”
d. Plain” females and “fabulous” males
e. “Fabulous” females and “smashing” males

Answer 25

c. All “fabulous”

Question 26

Suppose that the “fabulous” phenotype is controlled by two genes, A and B, as shown in the diagram below. Allele A produces enough enzyme 1 to convert “plain” to “smashing.” Allele a produces no enzyme 1. Allele B produces enough enzyme 2 to convert “smashing” to “fabulous.” Allele b produces no enzyme 2. The A and B genes are both autosomal and assort independently.

What will be the expected ratio of the F2 offspring of the F1 generation?

a. 9 “fabulous”:7 “plain”
b. 13 “fabulous”:3 “plain”
c. 9 “fabulous”:3 “smashing”:4 “plain”
d. 12 “plain”:3 “fabulous”:1 “smashing”
e. 15 “fabulous”:1 “smashing”

Answer 26

c. 9 “fabulous”:3 “smashing”:4 “plain”

Question 27

Coat color is determined by two loci in large cats. Two pink panthers fall in love and produce a large litter of baby panthers with the following phenotypic ratios: 12/16 pink; 3/16 black; and 1/16 white. What is the genotype of the pink progeny?

a. A_ B_
b. A_ bb
c. aa B_
d. aa bb
e. A_ B_ and A_ bb

Answer 27

e. A_ B_ and A_ bb

Question 28

Coat color is determined by two loci in large cats. Two pink panthers fall in love and produce a large litter of baby panthers with the following phenotypic ratios: 12/16 pink; 3/16 black; and 1/16 white. What is the genotype of the black progeny?

a. A_ B_
b. A_ bb
c. aa B_
d. aa bb
e. A_ B_ and A_ bb

Answer 28

c. aa B_

Question 29

Coat color is determined by two loci in large cats. Two pink panthers fall in love and produce a large litter of baby panthers with the following phenotypic ratios: 12/16 pink; 3/16 black; and 1/16 white. What is the genotype of the white progeny?

a. A_ B_
b. A_ bb
c. aa B_
d. aa bb
e. A_ B_ and A_ bb

Answer 29

d. aa bb

Question 30

Coat color is determined by two loci in large cats. Two pink panthers fall in love and produce a large litter of baby panthers with the following phenotypic ratios: 12/16 pink; 3/16 black; and 1/16 white. What kind of gene interaction is this?

a. Recessive epistasis
b. Dominant epistasis
c. Duplicate recessive epistasis
d. Duplicate dominant epistasis
e. Dominant and recessive epistasis

Answer 30

b. Dominant epistasis

Question 31

Two loci control body color in beetles. In a cross between a black beetle and a white beetle you obtain a ratio of 9 black to 7 white beetles. What kind of gene interaction is this?

a. Recessive epistasis
b. Dominant epistasis
c. Duplicate recessive epistasis
d. Duplicate dominant epistasis
e. Dominant and recessive epistasis

Answer 31

c. Duplicate recessive epistasis

Question 32

In order to determine if mutations from different organisms that exhibit the same phenotype are allelic, which test would you perform?

a. Test cross
b. Epistasis test
c. Complementation test
d. Allelic series test
e. Biochemical test

Answer 32

c. Complementation test

Question 33

In purple people eaters, purple is dominant to white. A true-breeding white mutant is mated with a different true-breeding white mutant. All of the F1 are purple. When the purple F1 offspring mate with each other, their offspring occur in the ratio of 9 purple:7 white. Which phenomenon explains the purple F1 offspring?

a. Recessive epistasis
b. Dominant epistasis
c. Complementation
d. Mutation
e. Suppression

Answer 33

c. Complementation

Question 34

The presence of a beard on some goats is determined by an autosomal gene that is dominant in males and recessive in females. Heterozygous males are bearded, while heterozygous females are beardless. What type of inheritance is exhibited by this trait?

a. Sex-linked
b. Sex-limited
c. Sex-influenced
d. Autosomal recessive
e. Autosomal dominant

Answer 34

d. Autosomal recessive

Question 35

In the yawncat (a rare hypothetical animal), the dominant allele R causes solid tail color, and the recessive allele r results in white spots on a colored background. The black coat color allele B is dominant to the brown allele b, but these genes can only be expressed if the animal has an mm genotype at a third gene locus. Animals that are M_ are yellow regardless of which allele from the B locus is present. A mating between a solid yellow-tailed male yawncat and a solid brown-tailed female yawncat produces 16 offspring with the following tail phenotypes: six solid yellow, two spotted yellow, three solid black, one spotted black, three solid brown, and one spotted brown. What is the most likely genotype of the male parent?

a. MM BB RR
b. MM Bb RR
c. Mm Bb RR
d. Mm BB Rr
e. Mm Bb Rr

Answer 35

e. Mm Bb Rr

Question 36

In the yawncat (a rare hypothetical animal), the dominant allele R causes solid tail color, and the recessive allele r results in white spots on a colored background. The black coat color allele B is dominant to the brown allele b, but these genes can only be expressed if the animal has an mm genotype at a third gene locus. Animals that are M_ are yellow regardless of which allele from the B locus is present. A mating between a solid yellow-tailed male yawncat and a solid brown-tailed female yawncat produces 16 offspring with the following tail phenotypes: six solid yellow, two spotted yellow, three solid black, one spotted black, three solid brown, and one spotted brown. What is the most likely genotype of the female parent?

a. mm bb rr
b. Mm bb rr
c. mm Bb rr
d. mm bb Rr
e. mm Bb Rr

Answer 36

d. mm bb Rr

Question 37

In the yawncat (a rare hypothetical animal), the dominant allele R causes solid tail color, and the recessive allele r results in white spots on a colored background. The black coat color allele B is dominant to the brown allele b, but these genes can only be expressed if the animal has an mm genotype at a third gene locus. Animals that are M_ are yellow regardless of which allele from the B locus is present. A mating between a solid yellow-tailed male yawncat and a solid brown-tailed female yawncat produces 16 offspring with the following tail phenotypes: six solid yellow, two spotted yellow, three solid black, one spotted black, three solid brown, and one spotted brown. What is the probability of the next offspring from these same two parents having a spotted brown tail?

a. 1/2
b. 3/16
c. 1/4
d. 1/16
e. 9/16

Answer 37

d. 1/16

Question 38

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. Give genotypes for comb shape of the parents in the following cross: Walnut crossed with single produces 1 walnut, 1 rose, 1 pea, and 1 single offspring.

a. RR PP × rr pp
b. RR Pp × rr pp
c. Rr PP × rr pp
d. Rr Pp × rr pp
e. Rr pp × rr pp

Answer 38

d. Rr Pp × rr pp

Question 39

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. Give genotypes for comb shape of the parents in the following cross: Rose crossed with pea produces 20 walnut offspring.

a. RR pp × rr PP
b. Rr pp × rr Pp
c. Rr pp × rr PP
d. RR pp × rr Pp
e. Rr pp × Rr Pp

Answer 39

a. RR pp × rr PP

Question 40

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. Give genotypes for comb shape of the parents in the following cross: Pea crossed with single produces 1 single offspring.

a. rr PP × rr pp
b. RR Pp × rr pp
c. Rr PP × rr pp
d. Rr Pp × rr pp
e. rr Pp × rr pp

Answer 40

e. rr Pp × rr pp

Question 41

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. Give genotypes for comb shape of the parents in the following cross: Rose crossed with pea produces 2 walnut, 1 single, and 1 pea offspring.

a. RR pp × rr PP
b. Rr pp × rr Pp
c. Rr pp × rr PP
d. RR pp × rr Pp
e. Rr pp × Rr Pp

Answer 41

b. Rr pp × rr Pp

Question 42

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. Give genotypes for comb shape of the parents in the following cross: Rose crossed with single produces 31 rose offspring.

a. RR PP × rr pp
b. RR pp × rr pp
c. Rr PP × rr pp
d. Rr Pp × rr pp
e. Rr pp × rr pp

Answer 42

b. RR pp × rr pp

Question 43

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. Give genotypes for comb shape of the parents in the following cross: Rose crossed with single produces 10 rose and 11 single offspring.

a. RR PP × rr pp
b. RR Pp × rr pp
c. Rr PP × rr pp
d. Rr Pp × rr pp
e. Rr pp × rr pp

Answer 43

e. Rr pp × rr pp

Question 44

In a certain species of plant, flowers occur in three colors: blue, pink, and white. A pure-breeding pink plant is mated with a pure-breeding white plant. All of the F1 are blue. When the blue F1 plants are selfed, the F2 occur in the ratio 9 blue:3 pink:4 white. How many gene pairs control the flower color phenotype?

a. 0
b. 1
c. 2
d. 3
e. 4

Answer 44

c. 2

Question 45

In a certain species of plant, flowers occur in three colors: blue, pink, and white. A pure-breeding pink plant is mated with a pure-breeding white plant. All of the F1 are blue. When the blue F1 plants are selfed, the F2 occur in the ratio 9 blue:3 pink:4 white. What is the name for this type of interaction?

a. Recessive epistasis
b. Dominant epistasis
c. Duplicate recessive epistasis
d. Duplicate dominant epistasis
e. Dominant and recessive epistasis

Answer 45

a. Recessive epistasis

Question 46

In a certain species of plant, flowers occur in three colors: blue, pink, and white. A pure-breeding pink plant is mated with a pure-breeding white plant. All of the F1 are blue. When the blue F1 plants are selfed, the F2 occur in the ratio 9 blue:3 pink:4 white. The genotype that produces white is ww. The presence of one W allele allows pink or blue color to occur. The alleles at the hypostatic locus are B (blue) and b (pink). What is the genotype of the pink parent?

a. bb WW
b. bb Ww
c. Bb Ww
d. Bb ww
e. BB ww

Answer 46

a. bb WW

Question 47

In a certain species of plant, flowers occur in three colors: blue, pink, and white. A pure-breeding pink plant is mated with a pure-breeding white plant. All of the F1 are blue. When the blue F1 plants are selfed, the F2 occur in the ratio 9 blue:3 pink:4 white. The genotype that produces white is ww. The presence of one W allele allows pink or blue color to occur. The alleles at the hypostatic locus are B (blue) and b (pink). What is the genotype of the white parent?

a. bb WW
b. bb Ww
c. Bb Ww
d. Bb ww
e. BB ww

Answer 47

a. bb WW

Question 48

In a certain species of plant, flowers occur in three colors: blue, pink, and white. A pure-breeding pink plant is mated with a pure-breeding white plant. All of the F1 are blue. When the blue F1 plants are selfed, the F2 occur in the ratio 9 blue:3 pink:4 white. The genotype that produces white is ww. The presence of one W allele allows pink or blue color to occur. The alleles at the hypostatic locus are B (blue) and b (pink). What is the genotype of the F1 plants?

a. bb WW
b. bb Ww
c. Bb Ww
d. Bb ww
e. BB ww

Answer 48

c. Bb Ww

Question 49

In domestic chickens, some males display a plumage pattern called cock feathering. Other males and all females display a pattern called hen feathering. Cock feathering is an autosomal recessive trait that is exhibited in males only. What type of inheritance is exhibited by this trait?

a. Sex-linked
b. Sex-limited
c. Sex-influenced
d. Autosomal recessive
e. Autosomal dominant

Answer 49

b. Sex-limited

Question 50

In domestic chickens, some males display a plumage pattern called cock feathering. Other males and all females display a pattern called hen feathering. Cock feathering is an autosomal recessive trait that is exhibited in males only. Two birds heterozygous for cock feathering are mated. What are the phenotypes of the parents?

a. Male with cock feathering, female with hen feathering
b. Male with hen feathering, female with cock feathering
c. Male with cock feathering, female with cock feathering
d. Male with hen feathering, female with hen feathering
e. Cannot be determined from the information given

Answer 50

d. Male with hen feathering, female with hen feathering