DBIA EXAM 1, EXAM 2 AND EXAM 3 NEWEST 2024
ACTUAL EXAM COMPLETE 500 QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |
ALREADY GRADED A+
All the offspring of a cross between a black-eyed Mendelian and an orange-eyed
Mendelian have black eyes. What is the expected phenotypic ratio of a cross
between two orange-eyed Mendelians?
A) 3 black-eyed: 1 orange-eyed
B) 0 black-eyed: 1 orange-eyed
C) 1 black-eyed: 3 orange-eyed
D) 1 black-eyed: 0 orange-eyed - ANSWER: B
If A is dominant to a and B is dominant to b, what is the expected phenotypic ratio of
the cross AaBb x AaBb?
A) 16:0:0:0
B) 8:4:2:2
C) 1:1:1:1
D) 9:3:3:1 - ANSWER: D
Using a six-sided die, what is the probability of rolling either a 5 or a 6?
A) 1/6 x 1/6 = 1/36
B) 1/6 + 1/6 = 1/3
C) 1/6 + 1/6 = 2/3 - ANSWER: B
Dr. Smith's parents have normal hearing. However, Dr. Smith has an inherited form
of deafness. Deafness is a recessive trait that is associated with the abnormal allele
d. The normal allele at this locus, associated with normal hearing, is D. Dr. Smith's
parents could have which of the following genotypes?
A) DD and dd
B) dd and dd
C) Dd and Dd
D) Dd and DD - ANSWER: C
Imagine that beak color in a finch species is controlled by a single gene. You mate a
finch homozygous for orange (pigmented) beak with a finch homozygous for ivory
(unpigmented) beak and get numerous offspring, all of which have a pale, ivory-
orange beak This pattern of color expression is most likely to be an example of
A) incomplete dominance
B) codominance
C) pleiotropy
D) polygenic inheritance - ANSWER: A
,A colorblind woman marries a man who is not colorblind. All of their sons, but none
of their daughters, are colorblind. Which of the following statements correctly
explains these results?
A) The gene for color vision is incompletely dominant to the gene for sex
determination
B) The gene for color vision is codominant with the gene for sex determination
C) The gene for color vision is found on the X chromosome
D) The gene for color vision is found on the Y chromosome - ANSWER: C
If independent assortment did not occur, which of the following would be true?
A) Genes for two different traits would be inherited together as a pair
B) Meiosis II would not be required to produce gametes, as meiosis I would be
sufficient
C) A dihybrid cross of heterozygous individuals would yield four different phenotypes
D) Each sperm and egg would carry more than one allele for a specific gene -
ANSWER: A
In giraffes, long necks (N), long legs (L), dark spots (D), and the ability to digest maize
(M) are all dominant traits. What possible genotype could a long-necked, short-
legged, light-spotted, maize-digesting giraffe have?
A) NnllddMM
B) NNLLDdMm
C) NNllddmm
D) nnLLddMM - ANSWER: A
Below are two statements: Which (if any) applies to the law of segregation? Which
(if any) applies to the law of independent assortment?
I: Phenotypes for long tails and big eyes are inherited separately in lab mice.
II: A baby mouse inherits a maternal red-eye allele and a paternal black-eye allele.
A) I: Segregation; II: Independent Assortment
B) I: Independent Assortment; II: Segregation
C) I: Segregation; II: Segregation
D) I: Independent Assortment; II: Independent Assortment - ANSWER: B
In some cats, black coat color (B) is dominant over brown (b) and a striped fur
pattern (S) is dominant over a marbled fur pattern (s). You rescued a black striped
cat from an animal shelter but could not determine its exact genotype. To do so, you
mated the cat with a brown marbled cat. The mating produced 3 brown marbled, 2
brown striped, 2 black marbled, and 3 black striped. Immediately, you concluded the
genotype of your rescued cat was
A) BBSS
B) BBSs
C) BbSS
D) BbSs - ANSWER: D
You are trying to determine the linkage map of a series of genes, X, Y, and Z, from
caenorhabditis elegans, a nematode worm commonly used in scientific research.
,From doing several crossover experiments, you know that the recombination
frequency between X and Y is 11.5%, between Y and Z is 13%, and between X and Z is
25%. What is the possible sequence of these genes?
A) X-Z-Y
B) Y-Z-X
C) Z-X-Y
D) X-Y-Z - ANSWER: D
Justin has type A blood and his wife Brittany has type B blood. Justin's parents both
have type AB blood, and Brittany's parents also both have type AB blood. What are
the chances that Justin and Brittany's son Theodore has type A blood?
A) 100%
B) 75%
C) 25%
D) 0% - ANSWER: D
What is the most likely explanation for the occurrence of an X-linked genetic
disorder in the boy at the bottom of the pedigree shown? (#25 on Chapter 9 Test)
A) The boy inherited this allele from this father only
B) The boy inherited this allele from his mother only
C) The boy inherited the kind of allele that skips every other generation
D) The boy has a new mutation for the disorder - ANSWER: D
How would the shape of a DNA molecule change if adenine paired with guanine and
cytosine paired with thymine?
A) The DNA molecule would be longer.
B) The DNA molecule would be shorter.
C) The DNA molecule would be circular.
D) The DNA molecule would have irregular widths along its length - ANSWER: D
The shape of a DNA molecule is most like
A) a set of railroad tracks
B) a wooden ladder
C) a twisted rope ladder
D) beads on a string - ANSWER: C
If one strand if DNA is CGGTAC, then the complementary strand would be
A) GCCTAG
B) GCCAUC
C) TAACGT
D) GCCATG - ANSWER: D
The copying mechanism of DNA is most like
A) taking a picture of yourself and of your reflection in a mirror
B) mixing flour, sugar, and water to make bread dough
C) looking at your reflection in a pool of water
D) carving a figure out of wood - ANSWER: A
, We would expect that a 15-nucleotide sequence that includes a stop codon at the
end (as part of the 15-nucleotide sequence) will direct the production of a
polypeptide that consists of
A) two amino acids
B) three amino acids
C) four amino acids
D) five amino acids - ANSWER: C
Consider the following sentence: " The dog did not eat." Which of the following
variations of this sentence is most like a frameshift mutation?
A) The did dog not eat
B) The dod idn ote at
C) The did not eat
D) The dog did dog did not eat - ANSWER: B
What is the transcription product of the sequence GCTAGCGATGAC?
A) CGTUCGCUTCUG
B) CGAUCGCUACUG
C) CAGTAGCGATCG
D) CGUTCGCUTCUG - ANSWER: B
A single base mutation occurs in a gene that codes for a protein due o an error in
DNA replication. Which of the following outcomes is not possible?
A) The mutation results in changed protein function
B) The mutation results in a longer or shorter protein or a protein of the same length
C) The mutation results in a human disease such as sickle-cell disease.
D) The mutation results in mRNA being made from the protein - ANSWER: D
It is possible to synthesize proteins in vitro ( in a test tube) without the use of living
cells. If starting from a mature mRNA transcript, which of the following components
would not be needed to do this?
A) adenine molecules
B) amino acids
C) tRNs
D) ribosomes - ANSWER: A
Normal genes have a promoter followed by a start codon. In a mutant gene, the "A"
in the start codon has been deleted. Which of the following is not a possible
outcome?
A) The normal protein will be produced
B) A shorter protein will be produced
C) A longer protein will be produced
D) No protein will be produced - ANSWER: A
(Use Chart on Chapter 10 #25) Using the genetic code shown, what protein sequence
does the RNA sequence CUAGCUCGAUAUCUC code for?
ACTUAL EXAM COMPLETE 500 QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |
ALREADY GRADED A+
All the offspring of a cross between a black-eyed Mendelian and an orange-eyed
Mendelian have black eyes. What is the expected phenotypic ratio of a cross
between two orange-eyed Mendelians?
A) 3 black-eyed: 1 orange-eyed
B) 0 black-eyed: 1 orange-eyed
C) 1 black-eyed: 3 orange-eyed
D) 1 black-eyed: 0 orange-eyed - ANSWER: B
If A is dominant to a and B is dominant to b, what is the expected phenotypic ratio of
the cross AaBb x AaBb?
A) 16:0:0:0
B) 8:4:2:2
C) 1:1:1:1
D) 9:3:3:1 - ANSWER: D
Using a six-sided die, what is the probability of rolling either a 5 or a 6?
A) 1/6 x 1/6 = 1/36
B) 1/6 + 1/6 = 1/3
C) 1/6 + 1/6 = 2/3 - ANSWER: B
Dr. Smith's parents have normal hearing. However, Dr. Smith has an inherited form
of deafness. Deafness is a recessive trait that is associated with the abnormal allele
d. The normal allele at this locus, associated with normal hearing, is D. Dr. Smith's
parents could have which of the following genotypes?
A) DD and dd
B) dd and dd
C) Dd and Dd
D) Dd and DD - ANSWER: C
Imagine that beak color in a finch species is controlled by a single gene. You mate a
finch homozygous for orange (pigmented) beak with a finch homozygous for ivory
(unpigmented) beak and get numerous offspring, all of which have a pale, ivory-
orange beak This pattern of color expression is most likely to be an example of
A) incomplete dominance
B) codominance
C) pleiotropy
D) polygenic inheritance - ANSWER: A
,A colorblind woman marries a man who is not colorblind. All of their sons, but none
of their daughters, are colorblind. Which of the following statements correctly
explains these results?
A) The gene for color vision is incompletely dominant to the gene for sex
determination
B) The gene for color vision is codominant with the gene for sex determination
C) The gene for color vision is found on the X chromosome
D) The gene for color vision is found on the Y chromosome - ANSWER: C
If independent assortment did not occur, which of the following would be true?
A) Genes for two different traits would be inherited together as a pair
B) Meiosis II would not be required to produce gametes, as meiosis I would be
sufficient
C) A dihybrid cross of heterozygous individuals would yield four different phenotypes
D) Each sperm and egg would carry more than one allele for a specific gene -
ANSWER: A
In giraffes, long necks (N), long legs (L), dark spots (D), and the ability to digest maize
(M) are all dominant traits. What possible genotype could a long-necked, short-
legged, light-spotted, maize-digesting giraffe have?
A) NnllddMM
B) NNLLDdMm
C) NNllddmm
D) nnLLddMM - ANSWER: A
Below are two statements: Which (if any) applies to the law of segregation? Which
(if any) applies to the law of independent assortment?
I: Phenotypes for long tails and big eyes are inherited separately in lab mice.
II: A baby mouse inherits a maternal red-eye allele and a paternal black-eye allele.
A) I: Segregation; II: Independent Assortment
B) I: Independent Assortment; II: Segregation
C) I: Segregation; II: Segregation
D) I: Independent Assortment; II: Independent Assortment - ANSWER: B
In some cats, black coat color (B) is dominant over brown (b) and a striped fur
pattern (S) is dominant over a marbled fur pattern (s). You rescued a black striped
cat from an animal shelter but could not determine its exact genotype. To do so, you
mated the cat with a brown marbled cat. The mating produced 3 brown marbled, 2
brown striped, 2 black marbled, and 3 black striped. Immediately, you concluded the
genotype of your rescued cat was
A) BBSS
B) BBSs
C) BbSS
D) BbSs - ANSWER: D
You are trying to determine the linkage map of a series of genes, X, Y, and Z, from
caenorhabditis elegans, a nematode worm commonly used in scientific research.
,From doing several crossover experiments, you know that the recombination
frequency between X and Y is 11.5%, between Y and Z is 13%, and between X and Z is
25%. What is the possible sequence of these genes?
A) X-Z-Y
B) Y-Z-X
C) Z-X-Y
D) X-Y-Z - ANSWER: D
Justin has type A blood and his wife Brittany has type B blood. Justin's parents both
have type AB blood, and Brittany's parents also both have type AB blood. What are
the chances that Justin and Brittany's son Theodore has type A blood?
A) 100%
B) 75%
C) 25%
D) 0% - ANSWER: D
What is the most likely explanation for the occurrence of an X-linked genetic
disorder in the boy at the bottom of the pedigree shown? (#25 on Chapter 9 Test)
A) The boy inherited this allele from this father only
B) The boy inherited this allele from his mother only
C) The boy inherited the kind of allele that skips every other generation
D) The boy has a new mutation for the disorder - ANSWER: D
How would the shape of a DNA molecule change if adenine paired with guanine and
cytosine paired with thymine?
A) The DNA molecule would be longer.
B) The DNA molecule would be shorter.
C) The DNA molecule would be circular.
D) The DNA molecule would have irregular widths along its length - ANSWER: D
The shape of a DNA molecule is most like
A) a set of railroad tracks
B) a wooden ladder
C) a twisted rope ladder
D) beads on a string - ANSWER: C
If one strand if DNA is CGGTAC, then the complementary strand would be
A) GCCTAG
B) GCCAUC
C) TAACGT
D) GCCATG - ANSWER: D
The copying mechanism of DNA is most like
A) taking a picture of yourself and of your reflection in a mirror
B) mixing flour, sugar, and water to make bread dough
C) looking at your reflection in a pool of water
D) carving a figure out of wood - ANSWER: A
, We would expect that a 15-nucleotide sequence that includes a stop codon at the
end (as part of the 15-nucleotide sequence) will direct the production of a
polypeptide that consists of
A) two amino acids
B) three amino acids
C) four amino acids
D) five amino acids - ANSWER: C
Consider the following sentence: " The dog did not eat." Which of the following
variations of this sentence is most like a frameshift mutation?
A) The did dog not eat
B) The dod idn ote at
C) The did not eat
D) The dog did dog did not eat - ANSWER: B
What is the transcription product of the sequence GCTAGCGATGAC?
A) CGTUCGCUTCUG
B) CGAUCGCUACUG
C) CAGTAGCGATCG
D) CGUTCGCUTCUG - ANSWER: B
A single base mutation occurs in a gene that codes for a protein due o an error in
DNA replication. Which of the following outcomes is not possible?
A) The mutation results in changed protein function
B) The mutation results in a longer or shorter protein or a protein of the same length
C) The mutation results in a human disease such as sickle-cell disease.
D) The mutation results in mRNA being made from the protein - ANSWER: D
It is possible to synthesize proteins in vitro ( in a test tube) without the use of living
cells. If starting from a mature mRNA transcript, which of the following components
would not be needed to do this?
A) adenine molecules
B) amino acids
C) tRNs
D) ribosomes - ANSWER: A
Normal genes have a promoter followed by a start codon. In a mutant gene, the "A"
in the start codon has been deleted. Which of the following is not a possible
outcome?
A) The normal protein will be produced
B) A shorter protein will be produced
C) A longer protein will be produced
D) No protein will be produced - ANSWER: A
(Use Chart on Chapter 10 #25) Using the genetic code shown, what protein sequence
does the RNA sequence CUAGCUCGAUAUCUC code for?
