©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
CMB 352 Genetics Exam 1 Questions With
Correct Answers
In lima beans, green color is dominant over yellow color. A cross between a pure green bean
and a pure yellow bean yields 40 hybrid beans. A cross between two of these hybrid beans
yielded 160 F2 beans. How many F2 beans should be yellow? - answer✔40
Mendel's unit factors of heredity are most accurately known to be: - answer✔two alleles for a
gene on a maternal an petal homologue of a homologous pair
If shape and color of gourds are determined by 2 genes with co-dominant alleles, crossing a
dihybrid heterozygote with a homozygous recessive will produce ___ different phenotypes. -
answer✔4
A couple has four children whose blood types are A, A, B and AB. Which of the following
parental genotypes are capable of producing the blood types of the couples' children? -
answer✔I^AI^O and I^BI^O
Following a SsYy x SsYy cross, what fraction of the offspring are predicted to have a genotype
that is heterozygous for both characteristics? - answer✔4/16
If X unites of of DNA are present in the nucleus of a cell, which has just divided, what is the
relative amount present in this cell during prophase of the next mitosis? - answer✔2X
A geocentric chromosome has its centromere located very close to, but not on, the end of the
chromosome. - answer✔false
A diploid cell of grasshopper: - answer✔has nice the amount of genetic information as the
haploid cell of a grasshopper
The number of genetically distinct gametes that an individual can produce is predicted: -
answer✔using the formula 2^N, where N equals the umber of heterozygous gene pairs
Pleiotrophy is: - answer✔when more than one phenotype results from the action of a single
gene
1|Page
, ©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
What is the difference between incomplete dominance and co-dominance? - answer✔In co-
dominance, both phenotypes are equally expressed in hybrids; in complete dominance, the
hybrid shows a new phenotype that is intermediate between the two homozygotes
Given incomplete dominance among the pairs of alleles at two of four loci and complete
dominance/recessiveness among the pairs of alleles at the other two loci, a cross between two
tetrahybrids will produce how many different phenotypes (assume independent assortment)
among the offspring? - answer✔36
Which of the following is a testcross? - answer✔aabb x AaBb
The idea that for any particular trait, the pair of alleles from each parent separate and only one
allele from each parent passes to an offspring is Mendel's principle of: - answer✔segregation
Epistasis: - answer✔is caused by genie interactions when two or more genes contribute to the
expression of a single trait
causes observance of non-Mendelian phenotypic segregation patterns in F2 populations
Dominant alleles always mask the effect of recessive alleles in the heterozygous condition -
answer✔true
The probability of independent events occurring together is the product of the probabilities of
the individual events occurring separately - answer✔true
Pure breeding lines are by definition homozygous for alleles of the genes being studied -
answer✔true
Independent assortment is an important mechanism for creating genetic diversity in somatic
cells - answer✔false
Cytokinesis segregates genetic information carried in cytoplasmic organelles such as vacuoles
and endoplasmic reticulum - answer✔false
Genotypic ratio of a monohybrid cross (without lethal alleles) in the F2 - answer✔J
1:2:1
Phenotypic ratio of a monohybrid cross with a recessive lethal allele in the F2 - answer✔A
2:1
Phenotypic ratio of a monohybrid testcross - answer✔E
1:1
2|Page
11/16/2024 10:16 AM
CMB 352 Genetics Exam 1 Questions With
Correct Answers
In lima beans, green color is dominant over yellow color. A cross between a pure green bean
and a pure yellow bean yields 40 hybrid beans. A cross between two of these hybrid beans
yielded 160 F2 beans. How many F2 beans should be yellow? - answer✔40
Mendel's unit factors of heredity are most accurately known to be: - answer✔two alleles for a
gene on a maternal an petal homologue of a homologous pair
If shape and color of gourds are determined by 2 genes with co-dominant alleles, crossing a
dihybrid heterozygote with a homozygous recessive will produce ___ different phenotypes. -
answer✔4
A couple has four children whose blood types are A, A, B and AB. Which of the following
parental genotypes are capable of producing the blood types of the couples' children? -
answer✔I^AI^O and I^BI^O
Following a SsYy x SsYy cross, what fraction of the offspring are predicted to have a genotype
that is heterozygous for both characteristics? - answer✔4/16
If X unites of of DNA are present in the nucleus of a cell, which has just divided, what is the
relative amount present in this cell during prophase of the next mitosis? - answer✔2X
A geocentric chromosome has its centromere located very close to, but not on, the end of the
chromosome. - answer✔false
A diploid cell of grasshopper: - answer✔has nice the amount of genetic information as the
haploid cell of a grasshopper
The number of genetically distinct gametes that an individual can produce is predicted: -
answer✔using the formula 2^N, where N equals the umber of heterozygous gene pairs
Pleiotrophy is: - answer✔when more than one phenotype results from the action of a single
gene
1|Page
, ©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
What is the difference between incomplete dominance and co-dominance? - answer✔In co-
dominance, both phenotypes are equally expressed in hybrids; in complete dominance, the
hybrid shows a new phenotype that is intermediate between the two homozygotes
Given incomplete dominance among the pairs of alleles at two of four loci and complete
dominance/recessiveness among the pairs of alleles at the other two loci, a cross between two
tetrahybrids will produce how many different phenotypes (assume independent assortment)
among the offspring? - answer✔36
Which of the following is a testcross? - answer✔aabb x AaBb
The idea that for any particular trait, the pair of alleles from each parent separate and only one
allele from each parent passes to an offspring is Mendel's principle of: - answer✔segregation
Epistasis: - answer✔is caused by genie interactions when two or more genes contribute to the
expression of a single trait
causes observance of non-Mendelian phenotypic segregation patterns in F2 populations
Dominant alleles always mask the effect of recessive alleles in the heterozygous condition -
answer✔true
The probability of independent events occurring together is the product of the probabilities of
the individual events occurring separately - answer✔true
Pure breeding lines are by definition homozygous for alleles of the genes being studied -
answer✔true
Independent assortment is an important mechanism for creating genetic diversity in somatic
cells - answer✔false
Cytokinesis segregates genetic information carried in cytoplasmic organelles such as vacuoles
and endoplasmic reticulum - answer✔false
Genotypic ratio of a monohybrid cross (without lethal alleles) in the F2 - answer✔J
1:2:1
Phenotypic ratio of a monohybrid cross with a recessive lethal allele in the F2 - answer✔A
2:1
Phenotypic ratio of a monohybrid testcross - answer✔E
1:1
2|Page
