TEST BANK for Introduction to Genetic
Analysis Complete Exam Multi Choice
Questions & Answers | updated 2025/2026 |
A+ Grades
If the DNA sequence on one strand is :
5'- ATGCCGTTA- 3'
i) What is the complementary strand?
ii) What does 5' and 3' mean? - answers 3'-TACGGCACT-5', the beginning and end of
the strand.
During DNA replication, the DNA is split, and paired up with a replicated strand of
complementary base pairs. Sometimes, this doesn't happen correctly. What errors
might occur during this process? - answers nucleotide bases may be inserted, deleted,
or mismatched into the DNA strand incorrectly
Why is DNA replication important for cell reproduction? Why is it important for the newly
replicated daughter strand of DNA to have the same information as the parent strands?
- answers Because all cells need DNA to function, it is important that the DNA from the
parent cell is copied to allow that same parent cell to divide into daughter cells. It is
pertinent that the DNA is the same in all the cells produced.
Explain how the leading and lagging strands of DNA are replicated. Include a drawing.
Be sure to explain why the lagging strand is more complicated to replicate. - answers
Both act as templates Replication fork moves down strand in 1 direction: leading strand
(continuous) is replicated into the fork and lagging strand goes in the opposite direction.
Why is DNA repair necessary? If DNA repair does not take place what could happen? -
answers DNA provides the blueprint for the proteins our cells need to function. Serious
damage could occur, including cancer.
How are multiple strands of mRNA synthesized? Why is it advantageous to make
multiple mRNA strands? - answers Multiple stands of mRNA can be made from a code
found in our DNA. If multiple mRNA strands are made an abundance of a specific
protein will be formed using the mRNA strand as the template to translate it into a
protein
Would errors in transcription or errors in replication be more damaging? Explain your
answer. - answers Errors in replication would be more damaging since this means the
error would be in the DNA. DNA is our code for hereditary/genetic information, as well
as ultimately the code for proteins. If the DNA is damaged and not properly fixed this
,change will "stick", every time the DNA is replicated the error will be replicated and this
could lead to a mutation.
Errors in transcription (DNA to RNA) would mean that the error is in the RNA strand,
this will impact the protein that should be translated from this mRNA strand, however
the "real" code is still present and available in our DNA to hopefully be transcribed
correctly next time.
What is the role of tRNA in translation? Why is there not a specific tRNA molecule for
each possible codon? - answers used as anticodon to convert into amino acid. There is
not a specific tRNA molecule for each possible codon because several codons code for
the same amino acid. If one tRNA recognizes each amino acid, then it can work
efficiently by recognizing all the codons that code for it. There are many more codons
than there are amino acids, but a unique tRNA molecule is not needed for each one.
Using words and/or diagrams, explain the process of translating mRNA to a polypeptide
- answers The ribosome binds to mRNA at a specific area.
The ribosome starts matching tRNA anticodon sequences to the mRNA codon
sequence.
Each time a new tRNA comes into the ribosome, the amino acid that it was carrying
gets added to the elongating polypeptide chain.
The ribosome continues until it hits a stop sequence, then it releases the polypeptide
and the mRNA.
The polypeptide forms into its native shape and starts acting as a functional protein in
the cell.
One of your friends tells you that he thinks biology is hard, and really doesn't get
genetics. How do you explain DNA replication, transcription and translation in a way that
will help him make sense of these very abstract concepts - answers Transcription is the
first step in gene expression. It involves copying a gene's DNA sequence to make an
RNA performed by enzymes called RNA polymerases, which links nitrogenous bases to
form an RNA strand (using a DNA strand as a template).
Describe the state of the trp operon system if the level of tryptophan is high. (discuss all
enzymes and proteins in the system). What would happen if tryptophan levels fall? -
answers When trp is high there is no need to make more, so the repressor which has
trp bound to it will attach to the operator stopping RNA polymerase from transcribing the
gene (trp is not made). When trp is low, trp will be made. Trp will fall off of the repressor
causing it to change shape and fall off the operator, allowing RNA polymerase to
transcribe the gene (make Trp)
Identify the similarities and the differences between the lac operon and the trp operon
systems. - answers Same level of gene control (transcriptional). They are both
regulated/controlled genes
Affected/altered by the amount of product present/available in the cell
The regulatory gene is where the repressor comes from
,Explain how a substitution, deletion or insertion can lead to a frameshift, point - answers
Base substitutions can create silent mutations (when the DNA change does not alter the
amino acid sequence), missense mutations (when the DNA change alters one single
amino acid) or nonsense mutations (when the DNA change creates a premature STOP
codon and truncates the amino acid chain).
Insertions or deletions can cause frameshift mutations since the addition or removal of a
base alters the reading frame and will affect every codon past the point of mutation (can
have a significant change in the amino acid chain).
Explain how translocation mutation and ultimately cause a silent, missense or nonsense
mutation to occur - answers Point mutations are changes to one base in the DNA code
and can be caused by:- Substitution (GAT becomes GCT)- Insertion (GAT becomes
GCAT)- Deletion (GAT becomes GT)- Inversion (GAT becomes GTA)
Translocation is when segments of 2 chromosomes are exchanged which can change
the gene sequences which can result in a large-scale change.
Some mutations may be inherited. What impact might this have? Consider ideas such
as disease, evolution, etc. Include a specific disease example in your answer, and a
specific example for evolution. - answers Harmful mutations may cause genetic
disorders or cancer. A genetic disorder is a disease caused by a mutation in one or a
few genes. A human example is cystic fibrosis. A mutation in a single gene causes the
body to produce thick, sticky mucus that clogs the lungs and blocks ducts in digestive
organs
A large portion of the human genome consists of non-coding introns. Hypothesize some
reasons that may explain this. - answers The amount of DNA contained inside each cell
is a large amount and not all of the genetic sequences present within a DNA molecule
actually code for a protein; this is because it allows a faster path to assemble new
genes. Which allows for transcription termination, and genome organization.
Many people believe that the size of a genome is directly related to the complexity of
the organism. Is this statement consistent with our present knowledge of DNA? -
answers Humans have the same DNA structure and coding as bacteria. The cell coding
carries out transcription and translation which allows a human gene to be expressed as
bacteria. DNA IS UNIVERSAL.
Why are restriction enzymes that produce DNA fragments with sticky ends more
valuable to geneticists than restriction enzymes that produce DNA fragments with blunt
ends? - answers Sticky ends are more useful in molecular cloning because they ensure
that the human DNA fragment is inserted into the plasmid in the right direction. The
ligation process, or fusing of DNA fragments, requires less DNA when the DNA have
sticky ends.
A plasmid was digested using restriction enzymes. The following DNA fragments were
produced: 1200 bp, 1800 bp, 200 bp, and 750 bp. Which fragment will travel the fastest
in an agarose gel? Why?
, Which fragment will travel the slowest in an agarose gel? Why? - answers The fragment
that will travel the fastest in the agarose gel is the 200 bp fragment. It will travel the
fastest because it is the smallest fragment.
The fragment that will travel the slowest in the agarose gel is the 1800bp because it is
the largest fragment.
A plasmid was digested using restriction enzymes. The following DNA fragments were
produced: 1200 bp, 1800 bp, 200 bp, and 750 bp. Sketch the gel pattern that would
result after running this plasmid digestion in an agarose gel.
What are some examples of when and/or why gel electrophoresis is used? - answers
The fragment that will travel the fastest in the agarose gel is the 200 bp fragment. It will
travel the fastest because it is the smallest fragment.
GENETICS- Chaviva Korb - answers
Lecture 1: - answers
- DNA is packaged as chromatin, chromosomes become visible during mitosis. -
answers
Homologues- (maternal and paternal forms of same chromosome) - answers
Meiosis: G1, S, G2, M. Before replication phase, chromosomes have one chromatid and
after replication, chromosomes have 2 sister chromatids, held together at the
centromere. Ends with 4 daughter cells with 1 chromatid each. - answers
Key differences from mitosis: Homologs pair (Prophase I), Sister centromeres act as a
single centromere (Metaphase I), Sister chromatids remain attached (Anaphase I),
Meiosis I is a reduction division- meaning start meiosis I with 46 units and end meiosis I
with 23 units ( 2 chromatids in each haploid daughter cells), Meiosis II is an equational
division (identical to mitosis). - answers
Recombination occurs in Prophase I. Crossing over and recomb is Exchange of
homologous segments between non-sister chromatids. - answers
Homologues move apart during anaphase I-disjunction. 223 possible combinations of
chromosomes. In cytokinesis I, Cells divide into two haploid daughter cells. One cell
receives most of the cytoplasm and the other becomes the first polar body which
doesn't go through Meiosis II. Meiosis I ends after ovulation. Non dysjunction in meiosis
I: can cause problems like Trisomy 21. - answers
-Brief interphase between first and second meiotic divisions. No S phase occurs in
Meiosis II. - answers
-In the second meiotic division a second polar body forms during oogenesis. In
oogenesis, egg is arrested in metaphase II until fertilization. - answers
Analysis Complete Exam Multi Choice
Questions & Answers | updated 2025/2026 |
A+ Grades
If the DNA sequence on one strand is :
5'- ATGCCGTTA- 3'
i) What is the complementary strand?
ii) What does 5' and 3' mean? - answers 3'-TACGGCACT-5', the beginning and end of
the strand.
During DNA replication, the DNA is split, and paired up with a replicated strand of
complementary base pairs. Sometimes, this doesn't happen correctly. What errors
might occur during this process? - answers nucleotide bases may be inserted, deleted,
or mismatched into the DNA strand incorrectly
Why is DNA replication important for cell reproduction? Why is it important for the newly
replicated daughter strand of DNA to have the same information as the parent strands?
- answers Because all cells need DNA to function, it is important that the DNA from the
parent cell is copied to allow that same parent cell to divide into daughter cells. It is
pertinent that the DNA is the same in all the cells produced.
Explain how the leading and lagging strands of DNA are replicated. Include a drawing.
Be sure to explain why the lagging strand is more complicated to replicate. - answers
Both act as templates Replication fork moves down strand in 1 direction: leading strand
(continuous) is replicated into the fork and lagging strand goes in the opposite direction.
Why is DNA repair necessary? If DNA repair does not take place what could happen? -
answers DNA provides the blueprint for the proteins our cells need to function. Serious
damage could occur, including cancer.
How are multiple strands of mRNA synthesized? Why is it advantageous to make
multiple mRNA strands? - answers Multiple stands of mRNA can be made from a code
found in our DNA. If multiple mRNA strands are made an abundance of a specific
protein will be formed using the mRNA strand as the template to translate it into a
protein
Would errors in transcription or errors in replication be more damaging? Explain your
answer. - answers Errors in replication would be more damaging since this means the
error would be in the DNA. DNA is our code for hereditary/genetic information, as well
as ultimately the code for proteins. If the DNA is damaged and not properly fixed this
,change will "stick", every time the DNA is replicated the error will be replicated and this
could lead to a mutation.
Errors in transcription (DNA to RNA) would mean that the error is in the RNA strand,
this will impact the protein that should be translated from this mRNA strand, however
the "real" code is still present and available in our DNA to hopefully be transcribed
correctly next time.
What is the role of tRNA in translation? Why is there not a specific tRNA molecule for
each possible codon? - answers used as anticodon to convert into amino acid. There is
not a specific tRNA molecule for each possible codon because several codons code for
the same amino acid. If one tRNA recognizes each amino acid, then it can work
efficiently by recognizing all the codons that code for it. There are many more codons
than there are amino acids, but a unique tRNA molecule is not needed for each one.
Using words and/or diagrams, explain the process of translating mRNA to a polypeptide
- answers The ribosome binds to mRNA at a specific area.
The ribosome starts matching tRNA anticodon sequences to the mRNA codon
sequence.
Each time a new tRNA comes into the ribosome, the amino acid that it was carrying
gets added to the elongating polypeptide chain.
The ribosome continues until it hits a stop sequence, then it releases the polypeptide
and the mRNA.
The polypeptide forms into its native shape and starts acting as a functional protein in
the cell.
One of your friends tells you that he thinks biology is hard, and really doesn't get
genetics. How do you explain DNA replication, transcription and translation in a way that
will help him make sense of these very abstract concepts - answers Transcription is the
first step in gene expression. It involves copying a gene's DNA sequence to make an
RNA performed by enzymes called RNA polymerases, which links nitrogenous bases to
form an RNA strand (using a DNA strand as a template).
Describe the state of the trp operon system if the level of tryptophan is high. (discuss all
enzymes and proteins in the system). What would happen if tryptophan levels fall? -
answers When trp is high there is no need to make more, so the repressor which has
trp bound to it will attach to the operator stopping RNA polymerase from transcribing the
gene (trp is not made). When trp is low, trp will be made. Trp will fall off of the repressor
causing it to change shape and fall off the operator, allowing RNA polymerase to
transcribe the gene (make Trp)
Identify the similarities and the differences between the lac operon and the trp operon
systems. - answers Same level of gene control (transcriptional). They are both
regulated/controlled genes
Affected/altered by the amount of product present/available in the cell
The regulatory gene is where the repressor comes from
,Explain how a substitution, deletion or insertion can lead to a frameshift, point - answers
Base substitutions can create silent mutations (when the DNA change does not alter the
amino acid sequence), missense mutations (when the DNA change alters one single
amino acid) or nonsense mutations (when the DNA change creates a premature STOP
codon and truncates the amino acid chain).
Insertions or deletions can cause frameshift mutations since the addition or removal of a
base alters the reading frame and will affect every codon past the point of mutation (can
have a significant change in the amino acid chain).
Explain how translocation mutation and ultimately cause a silent, missense or nonsense
mutation to occur - answers Point mutations are changes to one base in the DNA code
and can be caused by:- Substitution (GAT becomes GCT)- Insertion (GAT becomes
GCAT)- Deletion (GAT becomes GT)- Inversion (GAT becomes GTA)
Translocation is when segments of 2 chromosomes are exchanged which can change
the gene sequences which can result in a large-scale change.
Some mutations may be inherited. What impact might this have? Consider ideas such
as disease, evolution, etc. Include a specific disease example in your answer, and a
specific example for evolution. - answers Harmful mutations may cause genetic
disorders or cancer. A genetic disorder is a disease caused by a mutation in one or a
few genes. A human example is cystic fibrosis. A mutation in a single gene causes the
body to produce thick, sticky mucus that clogs the lungs and blocks ducts in digestive
organs
A large portion of the human genome consists of non-coding introns. Hypothesize some
reasons that may explain this. - answers The amount of DNA contained inside each cell
is a large amount and not all of the genetic sequences present within a DNA molecule
actually code for a protein; this is because it allows a faster path to assemble new
genes. Which allows for transcription termination, and genome organization.
Many people believe that the size of a genome is directly related to the complexity of
the organism. Is this statement consistent with our present knowledge of DNA? -
answers Humans have the same DNA structure and coding as bacteria. The cell coding
carries out transcription and translation which allows a human gene to be expressed as
bacteria. DNA IS UNIVERSAL.
Why are restriction enzymes that produce DNA fragments with sticky ends more
valuable to geneticists than restriction enzymes that produce DNA fragments with blunt
ends? - answers Sticky ends are more useful in molecular cloning because they ensure
that the human DNA fragment is inserted into the plasmid in the right direction. The
ligation process, or fusing of DNA fragments, requires less DNA when the DNA have
sticky ends.
A plasmid was digested using restriction enzymes. The following DNA fragments were
produced: 1200 bp, 1800 bp, 200 bp, and 750 bp. Which fragment will travel the fastest
in an agarose gel? Why?
, Which fragment will travel the slowest in an agarose gel? Why? - answers The fragment
that will travel the fastest in the agarose gel is the 200 bp fragment. It will travel the
fastest because it is the smallest fragment.
The fragment that will travel the slowest in the agarose gel is the 1800bp because it is
the largest fragment.
A plasmid was digested using restriction enzymes. The following DNA fragments were
produced: 1200 bp, 1800 bp, 200 bp, and 750 bp. Sketch the gel pattern that would
result after running this plasmid digestion in an agarose gel.
What are some examples of when and/or why gel electrophoresis is used? - answers
The fragment that will travel the fastest in the agarose gel is the 200 bp fragment. It will
travel the fastest because it is the smallest fragment.
GENETICS- Chaviva Korb - answers
Lecture 1: - answers
- DNA is packaged as chromatin, chromosomes become visible during mitosis. -
answers
Homologues- (maternal and paternal forms of same chromosome) - answers
Meiosis: G1, S, G2, M. Before replication phase, chromosomes have one chromatid and
after replication, chromosomes have 2 sister chromatids, held together at the
centromere. Ends with 4 daughter cells with 1 chromatid each. - answers
Key differences from mitosis: Homologs pair (Prophase I), Sister centromeres act as a
single centromere (Metaphase I), Sister chromatids remain attached (Anaphase I),
Meiosis I is a reduction division- meaning start meiosis I with 46 units and end meiosis I
with 23 units ( 2 chromatids in each haploid daughter cells), Meiosis II is an equational
division (identical to mitosis). - answers
Recombination occurs in Prophase I. Crossing over and recomb is Exchange of
homologous segments between non-sister chromatids. - answers
Homologues move apart during anaphase I-disjunction. 223 possible combinations of
chromosomes. In cytokinesis I, Cells divide into two haploid daughter cells. One cell
receives most of the cytoplasm and the other becomes the first polar body which
doesn't go through Meiosis II. Meiosis I ends after ovulation. Non dysjunction in meiosis
I: can cause problems like Trisomy 21. - answers
-Brief interphase between first and second meiotic divisions. No S phase occurs in
Meiosis II. - answers
-In the second meiotic division a second polar body forms during oogenesis. In
oogenesis, egg is arrested in metaphase II until fertilization. - answers
