BIO148 EXAM 3 RETAKE QUESTIONS
& ANSWERS
Which of the following statements about a pair of homologous chromosomes is FALSE?
- Correct Answers -They join together at fertilization
A heterozygous genetic locus consists of ... - Correct Answers -two different alleles for
the same gene.
Which of the following statements about the cells above is TRUE? (picture) - Correct
Answers -Cell 1 contains nonsister chromatids
Which of the following statements about nonhomologous chromosomes is TRUE? -
Correct Answers -They contain information for different traits
A diploid organism has 20 chromosomes (2n = 20). Which of the following describes a
cell at metaphase I of meiosis in this organism? - Correct Answers -It has 10 pairs of
homologous chromosomes and 40 DNA molecules
You are looking at germline cells of a fruit fly (a diploid organism). Which of these would
be true of a cell that is in some stage of meiosis I? - Correct Answers -Homologous
chromosomes are paired up and aligned at the metaphase plate
What proportion of the gametes produced by an individual with the genotype AaBb will
contain only dominant (upper case) alleles of the A and B genes? - Correct Answers -
1/4
One ____________ will contain two ___________ and many ______________ -
Correct Answers -replicated chromosome, DNA molecules, genes
A skin cell in a chimpanzee has 2n = 48 chromosomes. Which of the following is
CORRECT about the chimpanzee's cells? - Correct Answers -Its muscle cells have 24
different types of chromosomes
A diploid insect species has 42 chromosomes in a normal body cell. At the end of
Meiosis I, each cell has _____ chromosomes. After meiosis II and cytokinesis, each cell
has ____ chromosomes. - Correct Answers -21, 21
A diploid organism has 10 total chromosomes. A cell from this organism has 5 total
chromosomes and 10 DNA molecules. This cell could be at which of the following
stages of cell division? - Correct Answers -prophase II
, An individual with the genotype AaBB and an individual with the genotype AaBb both
make gametes. How many types of gametes will they have in common with respect to
alleles of these two genes? - Correct Answers -2
The A and B genes are located on different chromosomes. An individual with the
genotype AaBb undergoes meiosis. Which of the following could be a cell in prophase II
of meiosis in this individual? (picture) - Correct Answers -C
Which of the following statements about fertilization is TRUE? - Correct Answers -Two
haploid cells fuse to form a diploid cell
You are crossing individuals with the following genotypes:
Parent 1: YYRrParent 2: yyRr
How many different gamete types could they each make with respect to these two
genes? - Correct Answers -Parent 1: 2 types; Parent 2: 2 types
The stage of meiosis seen below is.... - Correct Answers -Anaphase I
The cell above is in a stage of meiosis. Each of the gametes made by the cell above will
have _____ chromosomes. - Correct Answers -3
An individual has the genotype AaBb. Genes A and B are on different chromosomes.
Which of the following chromosome arrangements would you NOT observe during a
normal meiosis? The dotted line represents the metaphase plate. - Correct Answers -D
Cells that have completed meiosis I and the first cytokinesis have _____ as cells that
are in G1 phase (before DNA replication). - Correct Answers -half the number of
chromosomes and the same number of DNA molecules
The figure above shows a zygote immediately after fertilization. Which of the following is
a possible description of the sperm and egg that fused to create this zygote? - Correct
Answers -The sperm was ER and the egg was er
A diploid plant has either pink or white flowers because of the alleles of a gene on
chromosome 6, and has either long or short stems because of the alleles of a gene on
chromosome 2. An individual is homozygous for the white-flower allele and
homozygous for the short-stem allele. What will its eggs contain? - Correct Answers -
one chromosome 6 with one white-flower allele and one chromosome 2 with one short-
stem allele
You have decided to become a professional dog breeder. Black color in dogs is
dominant to yellow color. You are unsure if your black dog is homozygous or
heterozygous. You decide to cross it to a pure breeding yellow dog. What phenotypic
results would you expect if the dog was homozygous? - Correct Answers -All puppies
would be black
& ANSWERS
Which of the following statements about a pair of homologous chromosomes is FALSE?
- Correct Answers -They join together at fertilization
A heterozygous genetic locus consists of ... - Correct Answers -two different alleles for
the same gene.
Which of the following statements about the cells above is TRUE? (picture) - Correct
Answers -Cell 1 contains nonsister chromatids
Which of the following statements about nonhomologous chromosomes is TRUE? -
Correct Answers -They contain information for different traits
A diploid organism has 20 chromosomes (2n = 20). Which of the following describes a
cell at metaphase I of meiosis in this organism? - Correct Answers -It has 10 pairs of
homologous chromosomes and 40 DNA molecules
You are looking at germline cells of a fruit fly (a diploid organism). Which of these would
be true of a cell that is in some stage of meiosis I? - Correct Answers -Homologous
chromosomes are paired up and aligned at the metaphase plate
What proportion of the gametes produced by an individual with the genotype AaBb will
contain only dominant (upper case) alleles of the A and B genes? - Correct Answers -
1/4
One ____________ will contain two ___________ and many ______________ -
Correct Answers -replicated chromosome, DNA molecules, genes
A skin cell in a chimpanzee has 2n = 48 chromosomes. Which of the following is
CORRECT about the chimpanzee's cells? - Correct Answers -Its muscle cells have 24
different types of chromosomes
A diploid insect species has 42 chromosomes in a normal body cell. At the end of
Meiosis I, each cell has _____ chromosomes. After meiosis II and cytokinesis, each cell
has ____ chromosomes. - Correct Answers -21, 21
A diploid organism has 10 total chromosomes. A cell from this organism has 5 total
chromosomes and 10 DNA molecules. This cell could be at which of the following
stages of cell division? - Correct Answers -prophase II
, An individual with the genotype AaBB and an individual with the genotype AaBb both
make gametes. How many types of gametes will they have in common with respect to
alleles of these two genes? - Correct Answers -2
The A and B genes are located on different chromosomes. An individual with the
genotype AaBb undergoes meiosis. Which of the following could be a cell in prophase II
of meiosis in this individual? (picture) - Correct Answers -C
Which of the following statements about fertilization is TRUE? - Correct Answers -Two
haploid cells fuse to form a diploid cell
You are crossing individuals with the following genotypes:
Parent 1: YYRrParent 2: yyRr
How many different gamete types could they each make with respect to these two
genes? - Correct Answers -Parent 1: 2 types; Parent 2: 2 types
The stage of meiosis seen below is.... - Correct Answers -Anaphase I
The cell above is in a stage of meiosis. Each of the gametes made by the cell above will
have _____ chromosomes. - Correct Answers -3
An individual has the genotype AaBb. Genes A and B are on different chromosomes.
Which of the following chromosome arrangements would you NOT observe during a
normal meiosis? The dotted line represents the metaphase plate. - Correct Answers -D
Cells that have completed meiosis I and the first cytokinesis have _____ as cells that
are in G1 phase (before DNA replication). - Correct Answers -half the number of
chromosomes and the same number of DNA molecules
The figure above shows a zygote immediately after fertilization. Which of the following is
a possible description of the sperm and egg that fused to create this zygote? - Correct
Answers -The sperm was ER and the egg was er
A diploid plant has either pink or white flowers because of the alleles of a gene on
chromosome 6, and has either long or short stems because of the alleles of a gene on
chromosome 2. An individual is homozygous for the white-flower allele and
homozygous for the short-stem allele. What will its eggs contain? - Correct Answers -
one chromosome 6 with one white-flower allele and one chromosome 2 with one short-
stem allele
You have decided to become a professional dog breeder. Black color in dogs is
dominant to yellow color. You are unsure if your black dog is homozygous or
heterozygous. You decide to cross it to a pure breeding yellow dog. What phenotypic
results would you expect if the dog was homozygous? - Correct Answers -All puppies
would be black
