BIOS 1700 Chapter 17 Test Questions
All Solved Correctly.
In fruit flies, what kind of eye color would be expressed in male progeny from a white-eyed
female and a red-eyed male?
Half of the male progeny would have red eyes and half of the male progeny would have white
eyes (1:1 ratio of eye color in males).
All males would have red eyes.
All males would have white eyes. - Answer All males would have white eyes
Inheritance due to a rare X-linked dominant mutation can be distinguished from inheritance due
to a rare autosomal dominant mutation because, in the X-linked case:
affected mothers do not have affected daughters.
the two possibilities cannot be distinguished.
affected mothers do not have affected sons.
affected fathers do not have affected sons.
affected fathers do not have affected daughters. - Answer affected father do not have
affected sons
When X-linked traits are recessive, males who express the trait:
receive the recessive allele from their fathers.
must receive recessive alleles from both parents.
receive the recessive allele from their mothers.
receive the recessive allele from their mothers and carry the recessive allele in their X
chromosomes.
carry the recessive allele in their X chromosome. - Answer receive the recessive allele from
their mothers and carry the recessive allele in their X chromosomes
A normal woman with a color-blind brother:
has a 50% chance of being heterozygous for the gene causing color blindness.
is herself heterozygous for the gene causing color blindness.
cannot carry the gene causing color blindness.
, has a 10% chance of being heterozygous for the gene causing color blindness.
has a 25% chance of being heterozygous for the gene causing color blindness. - Answer has
50% chance of being heterozygous for the gene causing color blindness
Four genes (A, B, C, and D) are in the same chromosome in the sequence D, A, B, and C. The
distance between A and B is 4 map units, between A and C is 6 map units, and between B and D
is 5 map units. The recombination frequency between genes C and D should be:
6%.
2%.
4%.
5%.
7%. - Answer 7%
Three genes (A, B, and C) are in the same chromosome. The distance between A and B is 1 map
unit, between B and C is 4 map units and between A and C is 3 map units. The CORRECT order
of genes in the chromosome is:
B C A.
A C B.
A B C.
B A C.
C B A. - Answer BAC
Hemophilia is a sex-linked recessive trait in humans. If a carrier female (heterozygous for the
trait) mated with a nonaffected male, what would be the expected outcome(s)?
None of the daughters would have hemophilia, and half of the sons would have hemophilia.
None of the daughters would have hemophilia.
None of the offspring would have hemophilia.
Half the sons would have hemophilia.
Half the daughters would have hemophilia. - Answer none of the daughters would have
hemophilia and half the sons would have hemophilia
Red-green color blindness is due to a mutant gene in the X chromosome. An XX female with
normal color vision and an XY male with normal color vision have a child with karyotype XXY
who is color blind. The likely explanation is that the:
All Solved Correctly.
In fruit flies, what kind of eye color would be expressed in male progeny from a white-eyed
female and a red-eyed male?
Half of the male progeny would have red eyes and half of the male progeny would have white
eyes (1:1 ratio of eye color in males).
All males would have red eyes.
All males would have white eyes. - Answer All males would have white eyes
Inheritance due to a rare X-linked dominant mutation can be distinguished from inheritance due
to a rare autosomal dominant mutation because, in the X-linked case:
affected mothers do not have affected daughters.
the two possibilities cannot be distinguished.
affected mothers do not have affected sons.
affected fathers do not have affected sons.
affected fathers do not have affected daughters. - Answer affected father do not have
affected sons
When X-linked traits are recessive, males who express the trait:
receive the recessive allele from their fathers.
must receive recessive alleles from both parents.
receive the recessive allele from their mothers.
receive the recessive allele from their mothers and carry the recessive allele in their X
chromosomes.
carry the recessive allele in their X chromosome. - Answer receive the recessive allele from
their mothers and carry the recessive allele in their X chromosomes
A normal woman with a color-blind brother:
has a 50% chance of being heterozygous for the gene causing color blindness.
is herself heterozygous for the gene causing color blindness.
cannot carry the gene causing color blindness.
, has a 10% chance of being heterozygous for the gene causing color blindness.
has a 25% chance of being heterozygous for the gene causing color blindness. - Answer has
50% chance of being heterozygous for the gene causing color blindness
Four genes (A, B, C, and D) are in the same chromosome in the sequence D, A, B, and C. The
distance between A and B is 4 map units, between A and C is 6 map units, and between B and D
is 5 map units. The recombination frequency between genes C and D should be:
6%.
2%.
4%.
5%.
7%. - Answer 7%
Three genes (A, B, and C) are in the same chromosome. The distance between A and B is 1 map
unit, between B and C is 4 map units and between A and C is 3 map units. The CORRECT order
of genes in the chromosome is:
B C A.
A C B.
A B C.
B A C.
C B A. - Answer BAC
Hemophilia is a sex-linked recessive trait in humans. If a carrier female (heterozygous for the
trait) mated with a nonaffected male, what would be the expected outcome(s)?
None of the daughters would have hemophilia, and half of the sons would have hemophilia.
None of the daughters would have hemophilia.
None of the offspring would have hemophilia.
Half the sons would have hemophilia.
Half the daughters would have hemophilia. - Answer none of the daughters would have
hemophilia and half the sons would have hemophilia
Red-green color blindness is due to a mutant gene in the X chromosome. An XX female with
normal color vision and an XY male with normal color vision have a child with karyotype XXY
who is color blind. The likely explanation is that the:
