IB 150 Exam 2 Questions With Complete Solutions
A group of black dogs with identical genotypes are crossed with
one another and produce 75% black puppies and 25% yellow
puppies. What is the genotype of the parents
A) BBEE
B) BbEE
C) BBEe
D) BbEe
E) BBee Correct Answers C) BBEe
A man and woman are both carriers for a recessive disorder
caused by a single gene. If a couple has exactly three children,
what is the probability that they will all be healthy (i.e., not have
the disorder)?
A) 0.015625
B) 0.125
C) 0.421875
D) 0.75
E) 2.25 Correct Answers C) 0.421875
A mother and father, who are both carriers for a rare, recessive
autosomal disorder, have three children without the disorder.
What is the probability their next child will have the disorder?
A) 0.0
B) 0.004
C) 0.0625
D) 0.105
,E) 0.25 Correct Answers E) 0.25
A particular recessive genetic disorder is caused by two
separate, unlinked genes (Genes E and F). To have the disorder,
a person mut be homozygous recessive for BOTH of these
genes. A mother is homozygous recessive for Gene E and
heterozygous for Gene F. The father is homozygous dominant
for Gene E and homozygous recessive for Gene F. IF they have
two children, what is the probability that one of them will have
this disorder?
A) 0.0
B) 0.0625
C) 0.125
D) 0.1875
E) 0.2 Correct Answers A) 0.0
A species of squirrel can have gray or black fur, and long or
short tails. Crosses between a group of black-furred, short-tailed
squirrel and a group of gray-furred, long-tailed squirrel produces
only black-furred, long-tailed offspring. The genes that
determine fur color and tail length are located on different
chromosome types.
How many different genotypes would be found among the
black-furred, long-tailed offspring produced in the described
cross (ccTT and CCtt)?
A) 1
B) 2
C) 4
, D) 8
E) 16 Correct Answers A) 1
A species of squirrel can have gray or black fur, and long or
short tails. Crosses between a group of black-furred, short-tailed
squirrel and a group of gray-furred, long-tailed squirrel produces
only black-furred, long-tailed offspring. The genes that
determine fur color and tail length are located on different
chromosome types.
How many different genotypes would be found among the
gametes of the black-furred, short-tailed parents?
A) 1
B) 2
C) 4
D) 8
E) 16 Correct Answers A) 1
A species of squirrel can have gray or black fur, and long or
short tails. Crosses between a group of black-furred, short-tailed
squirrel and a group of gray-furred, long-tailed squirrel produces
only black-furred, long-tailed offspring. The genes that
determine fur color and tail length are located on different
chromosome types.
Using the allele symbols C for black, c for gray, T for long and t
for short, what would be the genotype of the gray-furred, long-
tailed squirrels?
A) CCTT
A group of black dogs with identical genotypes are crossed with
one another and produce 75% black puppies and 25% yellow
puppies. What is the genotype of the parents
A) BBEE
B) BbEE
C) BBEe
D) BbEe
E) BBee Correct Answers C) BBEe
A man and woman are both carriers for a recessive disorder
caused by a single gene. If a couple has exactly three children,
what is the probability that they will all be healthy (i.e., not have
the disorder)?
A) 0.015625
B) 0.125
C) 0.421875
D) 0.75
E) 2.25 Correct Answers C) 0.421875
A mother and father, who are both carriers for a rare, recessive
autosomal disorder, have three children without the disorder.
What is the probability their next child will have the disorder?
A) 0.0
B) 0.004
C) 0.0625
D) 0.105
,E) 0.25 Correct Answers E) 0.25
A particular recessive genetic disorder is caused by two
separate, unlinked genes (Genes E and F). To have the disorder,
a person mut be homozygous recessive for BOTH of these
genes. A mother is homozygous recessive for Gene E and
heterozygous for Gene F. The father is homozygous dominant
for Gene E and homozygous recessive for Gene F. IF they have
two children, what is the probability that one of them will have
this disorder?
A) 0.0
B) 0.0625
C) 0.125
D) 0.1875
E) 0.2 Correct Answers A) 0.0
A species of squirrel can have gray or black fur, and long or
short tails. Crosses between a group of black-furred, short-tailed
squirrel and a group of gray-furred, long-tailed squirrel produces
only black-furred, long-tailed offspring. The genes that
determine fur color and tail length are located on different
chromosome types.
How many different genotypes would be found among the
black-furred, long-tailed offspring produced in the described
cross (ccTT and CCtt)?
A) 1
B) 2
C) 4
, D) 8
E) 16 Correct Answers A) 1
A species of squirrel can have gray or black fur, and long or
short tails. Crosses between a group of black-furred, short-tailed
squirrel and a group of gray-furred, long-tailed squirrel produces
only black-furred, long-tailed offspring. The genes that
determine fur color and tail length are located on different
chromosome types.
How many different genotypes would be found among the
gametes of the black-furred, short-tailed parents?
A) 1
B) 2
C) 4
D) 8
E) 16 Correct Answers A) 1
A species of squirrel can have gray or black fur, and long or
short tails. Crosses between a group of black-furred, short-tailed
squirrel and a group of gray-furred, long-tailed squirrel produces
only black-furred, long-tailed offspring. The genes that
determine fur color and tail length are located on different
chromosome types.
Using the allele symbols C for black, c for gray, T for long and t
for short, what would be the genotype of the gray-furred, long-
tailed squirrels?
A) CCTT
