BIO 340 Exam 2 Questions And 100%
Correct Answers A+ Graded
You purchase two strains of flowers of the same species, one strain that has only red
flowers and one that has only white flowers. You suspect both strains have been
obtained by self-crossing of only red and only white parents, respectively. Assume
flower colour is controlled by a single autosomal gene. You cross the red flowers with
the white flowers and all of the offspring are banded red and white. What can you say
about the alleles R and W of the flower color gene? ANSWER R and W are codominant
Your friend gets tested and the results are conclusive: she will not develop Huntington's
disease. What is the probability of her child having the disease now? ANSWER 0
Recessive mutations ANSWER The phenotype of a recessive mutation is seen only in
homozygous individuals.
Fully Dominant Mutations - ANSWER The phenotype of a fully dominant mutation is
expressed in heterozygous as well as homozygous individuals.
Loss-of-function mutations - ANSWER have the effect of losing some or all normal gene
function
hypomorphic, null - ANSWER type of mutation
hypomorphic mutations - ANSWER those mutations that have lost only some of their
function.
Null mutations - ANSWER those mutations that have lost all of their function
, haplosufficient - ANSWER where a a single copy is sufficient to produce the wild-type
phenotype in the heterozygous genotype
haploinsufficient - ANSWER a single copy is not sufficient to produce the wild-type
phenotype in the heterozygous genotype
gain-of-function - ANSWER in which the gene product acquires a new function or
express increased wild type activity
codominance - ANSWER both alleles for the same characteristic are simultaneously
expressed in the heterozygote
incomplete dominance - ANSWER one of the alleles appears in the phenotype in the
heterozygote, but not to the exclusion of the other, which can also be seen
Incomplete dominance. - ANSWER If black and white true-breeding mice are mated and
the result is all gray offspring, what inheritance pattern would this be indicative of?
Multiple alleles and codominance. - ANSWER ABO blood groups are an example of:
Yes, providing one i allele is contributed from each parent. - ANWER Can a child with
blood type O genotype ii be a legitimate child of parents where one of the parents had A
blood type and other had B?
incomplete dominance - ANSWER A white splashed (Bl/Bl) Andalausian chicken and a
black (bl/bl) Andalusian chicken are crossed. The heterozygotes produced show an
intermidiate phenotype (blue). What inheritance pattern would this be indicative of?
codominance - ANSWER A person with only one Sickle Cell Anemia allele and one
unaffected allele will have some normal red blood cells and some abnormal. What
inheritance pattern would this be indicative of?
complementation tests - EXPLANATION to see if any of the mutations are in the same
gene or whether each mutation is one of several genes required for the expression of a
phenotype.
Correct Answers A+ Graded
You purchase two strains of flowers of the same species, one strain that has only red
flowers and one that has only white flowers. You suspect both strains have been
obtained by self-crossing of only red and only white parents, respectively. Assume
flower colour is controlled by a single autosomal gene. You cross the red flowers with
the white flowers and all of the offspring are banded red and white. What can you say
about the alleles R and W of the flower color gene? ANSWER R and W are codominant
Your friend gets tested and the results are conclusive: she will not develop Huntington's
disease. What is the probability of her child having the disease now? ANSWER 0
Recessive mutations ANSWER The phenotype of a recessive mutation is seen only in
homozygous individuals.
Fully Dominant Mutations - ANSWER The phenotype of a fully dominant mutation is
expressed in heterozygous as well as homozygous individuals.
Loss-of-function mutations - ANSWER have the effect of losing some or all normal gene
function
hypomorphic, null - ANSWER type of mutation
hypomorphic mutations - ANSWER those mutations that have lost only some of their
function.
Null mutations - ANSWER those mutations that have lost all of their function
, haplosufficient - ANSWER where a a single copy is sufficient to produce the wild-type
phenotype in the heterozygous genotype
haploinsufficient - ANSWER a single copy is not sufficient to produce the wild-type
phenotype in the heterozygous genotype
gain-of-function - ANSWER in which the gene product acquires a new function or
express increased wild type activity
codominance - ANSWER both alleles for the same characteristic are simultaneously
expressed in the heterozygote
incomplete dominance - ANSWER one of the alleles appears in the phenotype in the
heterozygote, but not to the exclusion of the other, which can also be seen
Incomplete dominance. - ANSWER If black and white true-breeding mice are mated and
the result is all gray offspring, what inheritance pattern would this be indicative of?
Multiple alleles and codominance. - ANSWER ABO blood groups are an example of:
Yes, providing one i allele is contributed from each parent. - ANWER Can a child with
blood type O genotype ii be a legitimate child of parents where one of the parents had A
blood type and other had B?
incomplete dominance - ANSWER A white splashed (Bl/Bl) Andalausian chicken and a
black (bl/bl) Andalusian chicken are crossed. The heterozygotes produced show an
intermidiate phenotype (blue). What inheritance pattern would this be indicative of?
codominance - ANSWER A person with only one Sickle Cell Anemia allele and one
unaffected allele will have some normal red blood cells and some abnormal. What
inheritance pattern would this be indicative of?
complementation tests - EXPLANATION to see if any of the mutations are in the same
gene or whether each mutation is one of several genes required for the expression of a
phenotype.
