MMSC 491 EXAM 2 QUESTIONS WITH VERIFIED
ANSWERS
The term phenotype can be applied to a wide range of maifestations. Which of the
following protperties, if any do not constitute a phenotypic manifestation - Answers - The
sequance of a persons beta globin gene
Which, if any, of the following is incorrect? when used in human genetic - Answers -
Incorrect: The term dominant and recessive apply equally to allels and phenotypes
Correct:
- Dominant describes a phenotype that is manifestated in the heterozygotem that is, the
phenotype is attributed to just a single allele
-Recessive describes a phenotype that is manifest as a result of the combined effects of
boht alleles at a locus
-The AB blood group is an example of a co-dominant phenotype
With respect to autosomal recessive inheritance, which, if any, of the following
statements is incorrect - Answers - Incorrect: Heterozygotes are always asymptomatic
carriers
Correct:
-Affected individuals normally have unaffected parents
-for unaffected parents who have previously affected child, there is a 1 in 4 risk of
having an affected child on each occasion that they produce a new child
-Some affected individuals have alleles with idnetical pathogenic mutations but many
have two different mutant alleles and are described as compund heterozygotes
With respect to X-chromsome inactivation in females, which, if any of the following
statements is incorrect - Answers - Incorrect: The process involves epeigentic silencing
of each gene on one of the two x chromsomes, either the maternal X chromsome or the
paternal X chromsome
Correct
-X inactiavation first occurs in the preimplantation female mammalian embryo
-One of the two X chromsomes in each diploid cell of a normal women is randomly
selected to undergo X-inactation and becomes highly condensed
-Once the decision is made to inactavate a paternal X or the maternal X in a cell, all
descendant cells will continue with that pattern of X-inactivation
Wth respect to X-linked recessive inheritance, which, if any of the following statements
is false - Answers - False: Women are always asymptomatic
ANSWERS
The term phenotype can be applied to a wide range of maifestations. Which of the
following protperties, if any do not constitute a phenotypic manifestation - Answers - The
sequance of a persons beta globin gene
Which, if any, of the following is incorrect? when used in human genetic - Answers -
Incorrect: The term dominant and recessive apply equally to allels and phenotypes
Correct:
- Dominant describes a phenotype that is manifestated in the heterozygotem that is, the
phenotype is attributed to just a single allele
-Recessive describes a phenotype that is manifest as a result of the combined effects of
boht alleles at a locus
-The AB blood group is an example of a co-dominant phenotype
With respect to autosomal recessive inheritance, which, if any, of the following
statements is incorrect - Answers - Incorrect: Heterozygotes are always asymptomatic
carriers
Correct:
-Affected individuals normally have unaffected parents
-for unaffected parents who have previously affected child, there is a 1 in 4 risk of
having an affected child on each occasion that they produce a new child
-Some affected individuals have alleles with idnetical pathogenic mutations but many
have two different mutant alleles and are described as compund heterozygotes
With respect to X-chromsome inactivation in females, which, if any of the following
statements is incorrect - Answers - Incorrect: The process involves epeigentic silencing
of each gene on one of the two x chromsomes, either the maternal X chromsome or the
paternal X chromsome
Correct
-X inactiavation first occurs in the preimplantation female mammalian embryo
-One of the two X chromsomes in each diploid cell of a normal women is randomly
selected to undergo X-inactation and becomes highly condensed
-Once the decision is made to inactavate a paternal X or the maternal X in a cell, all
descendant cells will continue with that pattern of X-inactivation
Wth respect to X-linked recessive inheritance, which, if any of the following statements
is false - Answers - False: Women are always asymptomatic
