BIO 182 Exam 2 Questions & Answers 2023
In a simple Mendelian monohybrid cross, true-breeding tall plants are crossed
with short
plants, and the F1 plants, which are all tall, are allowed to self-pollinate. What
fraction of the F2 generation are both tall and heterozygous?
a. 1⁄8
b. 1⁄4
c. 1⁄3
d. 2⁄3
e. 1⁄2
e. 1⁄2
The phenotype of an individual
a. depends at least in part on the genotype.
b. is either homozygous or heterozygous.
c. determines the genotype.
d. is the genetic constitution of the organism.
e. is either monohybrid or dihybrid.
a. depends at least in part on the genotype.
The ABO blood groups in humans are determined by a multiple-allele system in
which IA and
IB are codominant and are both dominant to IO. A newborn infant is type A. The
mother is type
O. Possible phenotypes of the father are
a. A, B, or AB.
b. A, B, or O.
c. O only.
d. A or AB.
e. A or O
d. A or AB.
Which statement about an individual that is homozygous for an allele is not true?
a. Each of its cells possesses two copies of that allele.
b. Each of its gametes contains one copy of that allele.
c. It is true-breeding with respect to that allele.
d. Its parents were necessarily homozygous for that allele.
e. It can pass that allele to its offspring.
d. Its parents were necessarily homozygous for that allele.
Which statement about a test cross is not true?
a. It tests whether an unknown individual is homozygous or heterozygous.
b. The test individual is crossed with a homozygous recessive individual.
c. If the test individual is heterozygous, the progeny will have a 1:1 ratio.
d. If the test individual is homozygous, the progeny will have a 3:1 ratio.
e. Test cross results are consistent with Mendel's model of inheritance for
unlinked genes
d. If the test individual is homozygous, the progeny will have a 3:1 ratio
, Linked genes
a. must be immediately adjacent to one another on a chromosome.
b. have alleles that assort independently of one another.
c. never show crossing over.
d. are on the same chromosome.
e. always have multiple alleles.
d. are on the same chromosome.
In the F2 generation of a dihybrid cross
a. four phenotypes appear in the ratio 9:3:3:1 if the loci are linked.
b. four phenotypes appear in the ratio 9:3:3:1 if the loci are unlinked.
c. two phenotypes appear in the ratio 3:1 if the loci are unlinked.
d. three phenotypes appear in the ratio 1:2:1 if the loci are unlinked.
e. two phenotypes appear in the ratio 1:1 whether or not the loci are linked.
b. four phenotypes appear in the ratio 9:3:3:1 if the loci are unlinked.
The genetic sex of a human is determined by
a. ploidy, with the male being haploid.
b. the Y chromosome.
c. X and Y chromosomes, the male being XX.
d. the number of X chromosomes, the male being XO.
e. Z and W chromosomes, the male being ZZ.
b. the Y chromosome.
In epistasis
a. nothing changes from generation to generation.
b. one gene alters the effect of another.
c. a portion of a chromosome is deleted.
d. a portion of a chromosome is inverted.
e. the behavior of two genes is entirely independent
b. one gene alters the effect of another.
In humans, spotted teeth are caused by a dominant sex-linked gene. A man with
spotted teeth
whose father had normal teeth marries a woman with normal teeth. Therefore,
a. all of their daughters will have normal teeth.
b. all of their daughters will have spotted teeth.
c. all of their children will have spotted teeth.
d. half of their sons will have spotted teeth.
e. all of their sons will have spotted teeth.
b. all of their daughters will have spotted teeth.
A(n) _______ trait is one that can be passed from one generation to another.
heritable
A(n) _______ is an observable feature, such as flower color; a(n) _______ is a
particular form
of a character, such as a white flower
character; trait
A cross between two parents that differs by a single trait is a(n) _______ cross.
monohybrid
In a simple Mendelian monohybrid cross, true-breeding tall plants are crossed
with short
plants, and the F1 plants, which are all tall, are allowed to self-pollinate. What
fraction of the F2 generation are both tall and heterozygous?
a. 1⁄8
b. 1⁄4
c. 1⁄3
d. 2⁄3
e. 1⁄2
e. 1⁄2
The phenotype of an individual
a. depends at least in part on the genotype.
b. is either homozygous or heterozygous.
c. determines the genotype.
d. is the genetic constitution of the organism.
e. is either monohybrid or dihybrid.
a. depends at least in part on the genotype.
The ABO blood groups in humans are determined by a multiple-allele system in
which IA and
IB are codominant and are both dominant to IO. A newborn infant is type A. The
mother is type
O. Possible phenotypes of the father are
a. A, B, or AB.
b. A, B, or O.
c. O only.
d. A or AB.
e. A or O
d. A or AB.
Which statement about an individual that is homozygous for an allele is not true?
a. Each of its cells possesses two copies of that allele.
b. Each of its gametes contains one copy of that allele.
c. It is true-breeding with respect to that allele.
d. Its parents were necessarily homozygous for that allele.
e. It can pass that allele to its offspring.
d. Its parents were necessarily homozygous for that allele.
Which statement about a test cross is not true?
a. It tests whether an unknown individual is homozygous or heterozygous.
b. The test individual is crossed with a homozygous recessive individual.
c. If the test individual is heterozygous, the progeny will have a 1:1 ratio.
d. If the test individual is homozygous, the progeny will have a 3:1 ratio.
e. Test cross results are consistent with Mendel's model of inheritance for
unlinked genes
d. If the test individual is homozygous, the progeny will have a 3:1 ratio
, Linked genes
a. must be immediately adjacent to one another on a chromosome.
b. have alleles that assort independently of one another.
c. never show crossing over.
d. are on the same chromosome.
e. always have multiple alleles.
d. are on the same chromosome.
In the F2 generation of a dihybrid cross
a. four phenotypes appear in the ratio 9:3:3:1 if the loci are linked.
b. four phenotypes appear in the ratio 9:3:3:1 if the loci are unlinked.
c. two phenotypes appear in the ratio 3:1 if the loci are unlinked.
d. three phenotypes appear in the ratio 1:2:1 if the loci are unlinked.
e. two phenotypes appear in the ratio 1:1 whether or not the loci are linked.
b. four phenotypes appear in the ratio 9:3:3:1 if the loci are unlinked.
The genetic sex of a human is determined by
a. ploidy, with the male being haploid.
b. the Y chromosome.
c. X and Y chromosomes, the male being XX.
d. the number of X chromosomes, the male being XO.
e. Z and W chromosomes, the male being ZZ.
b. the Y chromosome.
In epistasis
a. nothing changes from generation to generation.
b. one gene alters the effect of another.
c. a portion of a chromosome is deleted.
d. a portion of a chromosome is inverted.
e. the behavior of two genes is entirely independent
b. one gene alters the effect of another.
In humans, spotted teeth are caused by a dominant sex-linked gene. A man with
spotted teeth
whose father had normal teeth marries a woman with normal teeth. Therefore,
a. all of their daughters will have normal teeth.
b. all of their daughters will have spotted teeth.
c. all of their children will have spotted teeth.
d. half of their sons will have spotted teeth.
e. all of their sons will have spotted teeth.
b. all of their daughters will have spotted teeth.
A(n) _______ trait is one that can be passed from one generation to another.
heritable
A(n) _______ is an observable feature, such as flower color; a(n) _______ is a
particular form
of a character, such as a white flower
character; trait
A cross between two parents that differs by a single trait is a(n) _______ cross.
monohybrid
