BIOL 4003 EXAM 1 || All Solved.
True-breeding tall plants with purple flowers are crossed to true-breeding dwarf plants with
white flowers. The F1 plants were tall with purple flowers. The genes that affect these traits
independently assort. If the F1 plants were crossed to dwarf plants with white flowers, the
expected ratio of the F2 generation would be correct answers 1 tall/white flowers : 1 tall/purple
flowers : 1 dwarf/white flowers : 1 dwarf/ purple flowers
Which event during meiosis explains Mendel's law of segregation? correct answers Separation of
homologs during anaphase I of meiosis
Which of the following is a molecular explanation for the effects of a rare allele that is dominant
over the normal (wild-type) allele?
a. haploinsufficiency
b. gain-of-function mutation
c. dominant negative mutation
d. All of the other 3 choices are possible. correct answers All of the other 3 choices are possible.
Red/green colorblindness is an X-linked recessive trait. A mother with normal vision and a father
with red/green colorblindness have a daughter with red/green colorblindness. Assuming that an
offspring can be male or female, what is the probability that their next child will be a male with
red/green colorblindness? correct answers 25%
A cross is made between two individuals that are AaBbCcDd. What is the probability that an
offspring will be AaBbCcDD? correct answers 1/32
A type B woman is the daughter of a type O father and type B mother. If she has children with a
type O man, what is the probability of having a child with type O blood? correct answers 50%
, In chickens, brown feathers is dominant to white feathers. Let's suppose a heterozygote is
crossed to a chicken with white feathers. What is the probability of having three offspring, 2
offspring will have brown feathers and 1 with white? correct answers 0.375
The length of the index finger is sex-influenced. The short allele is dominant in males, whereas
the long allele is dominant in females. If a heterozygous male and a female with short index
fingers have offspring together, what are the possible phenotypes of the offspring? correct
answers males with short index fingers and females with short or long index fingers
Two different strains of plant exhibit a recessive phenotype of white flowers. When crossed, they
produce offspring with wild-type purple flowers. The outcome of this cross is called
______________ and it indicates that _________________________________. correct answers
complementation/the recessive alleles are in two different genes.
In (placental) mammals such as people, the process of X chromosome inactivation correct
answers causes the formation of a Barr body.
In mice, a true-breeding female with a normal tail is crossed to a true-breeding male with a short
tail. All of the F1 offspring have normal tails. The F1 female offspring are then crossed to true-
breeding males with a short tail. All of the F2 offspring have normal tails. These are observations
are consistent with correct answers both maternal effect and maternal inheritance.
The Igf2 gene that is inherited from the mother is silenced due to imprinting. A mutation, which
we will call Igf2—, is a loss-of-function mutation. If an Igf2 Igf2— mother is crossed to an Igf2
Igf2 father, what is the predicted outcome? correct answers All offspring would be normal.
In snails, coiling is controlled by a maternal effect gene in which D (right) is dominant to d (left)
A female that coils to the left has offspring that coil to the right. What are the genotypes of the
mother of these offspring and the maternal grandmother, respectively? correct answers Dd, ddv
With regard to a maternal effect gene, a mother is Dd and a haploid oocyte produced by the
mother is d. Which gene products would be found in this oocyte? correct answers Both D and d
gene products
True-breeding tall plants with purple flowers are crossed to true-breeding dwarf plants with
white flowers. The F1 plants were tall with purple flowers. The genes that affect these traits
independently assort. If the F1 plants were crossed to dwarf plants with white flowers, the
expected ratio of the F2 generation would be correct answers 1 tall/white flowers : 1 tall/purple
flowers : 1 dwarf/white flowers : 1 dwarf/ purple flowers
Which event during meiosis explains Mendel's law of segregation? correct answers Separation of
homologs during anaphase I of meiosis
Which of the following is a molecular explanation for the effects of a rare allele that is dominant
over the normal (wild-type) allele?
a. haploinsufficiency
b. gain-of-function mutation
c. dominant negative mutation
d. All of the other 3 choices are possible. correct answers All of the other 3 choices are possible.
Red/green colorblindness is an X-linked recessive trait. A mother with normal vision and a father
with red/green colorblindness have a daughter with red/green colorblindness. Assuming that an
offspring can be male or female, what is the probability that their next child will be a male with
red/green colorblindness? correct answers 25%
A cross is made between two individuals that are AaBbCcDd. What is the probability that an
offspring will be AaBbCcDD? correct answers 1/32
A type B woman is the daughter of a type O father and type B mother. If she has children with a
type O man, what is the probability of having a child with type O blood? correct answers 50%
, In chickens, brown feathers is dominant to white feathers. Let's suppose a heterozygote is
crossed to a chicken with white feathers. What is the probability of having three offspring, 2
offspring will have brown feathers and 1 with white? correct answers 0.375
The length of the index finger is sex-influenced. The short allele is dominant in males, whereas
the long allele is dominant in females. If a heterozygous male and a female with short index
fingers have offspring together, what are the possible phenotypes of the offspring? correct
answers males with short index fingers and females with short or long index fingers
Two different strains of plant exhibit a recessive phenotype of white flowers. When crossed, they
produce offspring with wild-type purple flowers. The outcome of this cross is called
______________ and it indicates that _________________________________. correct answers
complementation/the recessive alleles are in two different genes.
In (placental) mammals such as people, the process of X chromosome inactivation correct
answers causes the formation of a Barr body.
In mice, a true-breeding female with a normal tail is crossed to a true-breeding male with a short
tail. All of the F1 offspring have normal tails. The F1 female offspring are then crossed to true-
breeding males with a short tail. All of the F2 offspring have normal tails. These are observations
are consistent with correct answers both maternal effect and maternal inheritance.
The Igf2 gene that is inherited from the mother is silenced due to imprinting. A mutation, which
we will call Igf2—, is a loss-of-function mutation. If an Igf2 Igf2— mother is crossed to an Igf2
Igf2 father, what is the predicted outcome? correct answers All offspring would be normal.
In snails, coiling is controlled by a maternal effect gene in which D (right) is dominant to d (left)
A female that coils to the left has offspring that coil to the right. What are the genotypes of the
mother of these offspring and the maternal grandmother, respectively? correct answers Dd, ddv
With regard to a maternal effect gene, a mother is Dd and a haploid oocyte produced by the
mother is d. Which gene products would be found in this oocyte? correct answers Both D and d
gene products
