ANSC 221 Exam 3 Questions with All
Solved Solutions 2026-2027 Updated.
An individual that has the same allele of a gene on both chromosomes is said to be: - Answer
homozygous
If the SsWw individual is mated with another SsWw individual, what is the probability of
producing a SSWW offspring? - Answer 1/16
A geneticist finds that a gene that gives werewolves long fangs also makes them extra hairy. This
is an example of: - Answer pleiotropy
A situation where alleles at one gene influence the phenotypic expression of alleles of another
gene would be called: - Answer epistasis
Selected genotypes at the BRCA1 locus in humans have been shown to cause breast cancer in
women. However, not all women with predisposing genotypes will get breast cancer. This is an
example of - Answer penetrance
Based on Mendel's experimental crosses, what is the expected F2 phenotypic ratio of a cross
between two individuals who are both heterozygous for two independently assorting genes? -
Answer 9:3:3:1
Given the corn plant with the genotype AaBb, what is the probability of the first plant produced
through selfing having the genotype AaBB? - Answer 1/8
You capture several interesting insects from a population in your yard. By inbreeding, you
develop true breeding strains that differ only in the shape of their wings - one strain has round
wings while the other strain has oval wings. How might you demonstrate that Mendel's
principles apply to your insects? - Answer Set up a dihybrid cross and determine if your F2
results are predicted by a 9:3:3:1 ratio based on the law of independent assortment
The dominance hierarchy is as follows: C > c chinchilla > c himilayan > c. What is the predicted
phenotype ratio for the offspring of a cross between a chinchilla rabbit heterozygous for the
himalyan allele and a himilayan rabbit heterozygous for the albino allele? - Answer 1/2
chinchilla, 1/2 himalayan
In a family with four offspring and both parents heterozygous, what is the probability of finding
the oldest offspring white, while all the others black? (B_ is dominant and bb is recessive) -
Answer 27/256
, In the family with four offspring and both parents heterozygous, what is the probability of
finding one white and three black offspring? - Answer 42.2%
Billy Bob: A
Betty Lou: B
Baby: A
These results show: - Answer Billy Bob may or may not be the father, more testing is needed
A pair of co-dominant sex linked alleles in mammals produces red pigment when homozygous
or hemizygous for A1, white when homozygous or hemizygous for A2, and pink when
heterzygous. If a pink female is mated to a white male, we expect progeny: - Answer 50% of all
females are white
During a ________ cross, an individual with the dominant phenotype and unknown genotype is
crossed with a ________ individual to determine the unknown genotype. - Answer test;
homozygous recessive
Could a recessive mutation in humans be located on the X chromosome if a woman exhibiting
the trait marries a normal man and has a normal son? - Answer Probably not
A homozygous 4 o'clock plant with red flowers is crossed to a homozygous 4 o'clock plant with
white flowers. The F1 hybrid is pink flowered and the F2 plants segregate 1 red to 2 pink and to
1 white. This is an example of: - Answer incomplete dominance
Two mothers give birth to sons at the same time at a busy hospital. The son of couple 1 is
diagnosed as having hemophilia, a disease caused by an X-linked recessive allele. However,
neither of the parents is affected. Couple 2 has a normal son despite the fact that the father has
hemophilia. Several years later, couple 1 decides to sue the hospital claiming that the newborns
where switched at birth. Once again, you are asked to be a genetic consultant. What
information can you share with the jury in regards to the allegations of couple 1 - Answer a.
Because hemophilia is X-linked recessive, the mother in couple 1 could be heterozygous even
though she is normal
c. The x chromosome in male offspring is inherited from the mother, therefore even if the father
has hemophilia he would not pass it to his son.
(Both a and c)
Solved Solutions 2026-2027 Updated.
An individual that has the same allele of a gene on both chromosomes is said to be: - Answer
homozygous
If the SsWw individual is mated with another SsWw individual, what is the probability of
producing a SSWW offspring? - Answer 1/16
A geneticist finds that a gene that gives werewolves long fangs also makes them extra hairy. This
is an example of: - Answer pleiotropy
A situation where alleles at one gene influence the phenotypic expression of alleles of another
gene would be called: - Answer epistasis
Selected genotypes at the BRCA1 locus in humans have been shown to cause breast cancer in
women. However, not all women with predisposing genotypes will get breast cancer. This is an
example of - Answer penetrance
Based on Mendel's experimental crosses, what is the expected F2 phenotypic ratio of a cross
between two individuals who are both heterozygous for two independently assorting genes? -
Answer 9:3:3:1
Given the corn plant with the genotype AaBb, what is the probability of the first plant produced
through selfing having the genotype AaBB? - Answer 1/8
You capture several interesting insects from a population in your yard. By inbreeding, you
develop true breeding strains that differ only in the shape of their wings - one strain has round
wings while the other strain has oval wings. How might you demonstrate that Mendel's
principles apply to your insects? - Answer Set up a dihybrid cross and determine if your F2
results are predicted by a 9:3:3:1 ratio based on the law of independent assortment
The dominance hierarchy is as follows: C > c chinchilla > c himilayan > c. What is the predicted
phenotype ratio for the offspring of a cross between a chinchilla rabbit heterozygous for the
himalyan allele and a himilayan rabbit heterozygous for the albino allele? - Answer 1/2
chinchilla, 1/2 himalayan
In a family with four offspring and both parents heterozygous, what is the probability of finding
the oldest offspring white, while all the others black? (B_ is dominant and bb is recessive) -
Answer 27/256
, In the family with four offspring and both parents heterozygous, what is the probability of
finding one white and three black offspring? - Answer 42.2%
Billy Bob: A
Betty Lou: B
Baby: A
These results show: - Answer Billy Bob may or may not be the father, more testing is needed
A pair of co-dominant sex linked alleles in mammals produces red pigment when homozygous
or hemizygous for A1, white when homozygous or hemizygous for A2, and pink when
heterzygous. If a pink female is mated to a white male, we expect progeny: - Answer 50% of all
females are white
During a ________ cross, an individual with the dominant phenotype and unknown genotype is
crossed with a ________ individual to determine the unknown genotype. - Answer test;
homozygous recessive
Could a recessive mutation in humans be located on the X chromosome if a woman exhibiting
the trait marries a normal man and has a normal son? - Answer Probably not
A homozygous 4 o'clock plant with red flowers is crossed to a homozygous 4 o'clock plant with
white flowers. The F1 hybrid is pink flowered and the F2 plants segregate 1 red to 2 pink and to
1 white. This is an example of: - Answer incomplete dominance
Two mothers give birth to sons at the same time at a busy hospital. The son of couple 1 is
diagnosed as having hemophilia, a disease caused by an X-linked recessive allele. However,
neither of the parents is affected. Couple 2 has a normal son despite the fact that the father has
hemophilia. Several years later, couple 1 decides to sue the hospital claiming that the newborns
where switched at birth. Once again, you are asked to be a genetic consultant. What
information can you share with the jury in regards to the allegations of couple 1 - Answer a.
Because hemophilia is X-linked recessive, the mother in couple 1 could be heterozygous even
though she is normal
c. The x chromosome in male offspring is inherited from the mother, therefore even if the father
has hemophilia he would not pass it to his son.
(Both a and c)
