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BIO 340 Holechek Exam 3
Questions & Answers
2026/2027 | Arizona State
University | Comprehensive
Review (Rationales)
Document Overview
This comprehensive review document for BIO 340 at Arizona State University
contains 53 questions with provided correct answers and detailed rationales,
covering core molecular biology concepts. It is ideal for students preparing for
exams, reviewing course material, or seeking certification, offering a direct
pathway to understanding key principles through pre-answered questions and
explanations.
100% Accurate Questions and Answers
100% Guarantee Pass - Verified by Experts Expert-Verified
Verified Answers · Detailed Rationales · 53 Questions · September 2026
BIO 340 Holechek Exam 3 Questions & Answers 2026/2027 | Arizona State University | Comprehensive Review (Rationales) - Practice Questions Page 0
, Topics Covered
Section 1: Molecular Biology Techniques Q 1-25
Questions covering molecular Biology Techniques concepts.
Section 2: Genetic Transfer and Resistance Q 26-33
Questions covering genetic Transfer and Resistance concepts.
Section 3: Genetic Testing and Applications Q 34-41
Questions covering genetic Testing and Applications concepts.
Section 4: Genomics and Human Genetics Q 42-53
Questions covering genomics and Human Genetics concepts.
Questions
QUESTION 1 OF 53
PCR
Correct Answer: This technique uses an extremophile in order to replicate DNA quickly.
Rationale: Polymerase Chain Reaction (PCR) relies on thermostable DNA polymerases, such as Taq polymerase
derived from the thermophilic bacterium *Thermus aquaticus*, to withstand the high temperatures required for DNA
denaturation during the cycling process. This heat resistance allows for repeated cycles of denaturation, annealing,
and extension, enabling rapid amplification of specific DNA sequences. The use of such extremophile enzymes is
fundamental to the efficiency and speed of PCR. This aligns with This technique uses an extremophile in order to
replicate DNA quickly..
QUESTION 2 OF 53
denaturation
Correct Answer: The first thing that happens to DNA during the PCR process is ____?
Rationale: During the initial step of Polymerase Chain Reaction (PCR), the double-stranded DNA template is heated
to a high temperature, typically between 94-98°C. This high temperature breaks the hydrogen bonds holding the two
complementary strands together, causing them to separate into single strands. This process is known as denaturation.
This aligns with The first thing that happens to DNA during the PCR process is ____?.
QUESTION 3 OF 53
primer annealing
Correct Answer: The second thing that happens during the PCR process is ____?
Rationale: Primer annealing is the step in Polymerase Chain Reaction (PCR) where short DNA sequences, the
primers, bind to complementary regions on the single-stranded template DNA. This binding occurs after denaturation,
where the DNA is heated to separate strands, and before extension, where DNA polymerase synthesizes new strands.
This precise binding allows for targeted amplification of specific DNA segments. This aligns with The second thing that
happens during the PCR process is ____?.
BIO 340 Holechek Exam 3 Questions & Answers 2026/2027 | Arizona State University | Comprehensive Review (Rationales) - Practice Questions Page 0
, QUESTION 4 OF 53
primer annealing
Correct Answer: phase in PCR during which a primer binds to a template strand
Rationale: Primer annealing is a critical step in the polymerase chain reaction (PCR) process. During this phase,
short, synthetic DNA sequences known as primers bind specifically to complementary regions on the denatured
template DNA strands. This binding is essential for DNA polymerase to initiate DNA synthesis and amplify the target
sequence. This aligns with phase in PCR during which a primer binds to a template strand.
QUESTION 5 OF 53
extension
Correct Answer: The final step of the PCR process is termed ____?
Rationale: The final step of the PCR process is termed ____?, after denaturation and annealing, the DNA
polymerase synthesizes new DNA strands. This synthesis step, where the enzyme extends the primer along the
template, is called the extension or elongation phase. Therefore, extension is the final step of the PCR process.
QUESTION 6 OF 53
negative
Correct Answer: what type of electric charge does DNA have?
Rationale: DNA possesses a negative electric charge due to the phosphate groups in its sugar-phosphate backbone.
These phosphate groups are deprotonated at physiological pH, leaving them with a net negative charge. This aligns
with what type of electric charge does DNA have?.
QUESTION 7 OF 53
size
Correct Answer: Other than charge what is a crucial component of DNA during gel electrophoresis?
Rationale: Other than charge what is a crucial component of DNA during gel electrophoresis?, DNA fragments
migrate through the porous gel matrix. While charge (due to the phosphate backbone) dictates the direction of
migration towards the positive electrode, the *size* of the DNA fragment determines its speed of movement. Smaller
fragments navigate the gel matrix more easily and thus travel further than larger fragments in a given amount of
time.
QUESTION 8 OF 53
Probes
Correct Answer: Short DNA fragments that can be stained with something such as a radioactive dye in
order to further understand DNA are called
Rationale: Short DNA fragments that can be stained with something such as a radioactive dye in order to further
understand DNA are called, labeled nucleic acid sequences used in molecular biology techniques like Southern blotting
or in situ hybridization to detect specific DNA or RNA sequences. The radioactive dye or other label allows for
visualization and identification of the target sequence within a larger sample. Therefore, DNA fragments stained for
identification are correctly identified as probes.
BIO 340 Holechek Exam 3 Questions & Answers 2026/2027 | Arizona State University | Comprehensive Review (Rationales) - Practice Questions Page 0
BIO 340 Holechek Exam 3
Questions & Answers
2026/2027 | Arizona State
University | Comprehensive
Review (Rationales)
Document Overview
This comprehensive review document for BIO 340 at Arizona State University
contains 53 questions with provided correct answers and detailed rationales,
covering core molecular biology concepts. It is ideal for students preparing for
exams, reviewing course material, or seeking certification, offering a direct
pathway to understanding key principles through pre-answered questions and
explanations.
100% Accurate Questions and Answers
100% Guarantee Pass - Verified by Experts Expert-Verified
Verified Answers · Detailed Rationales · 53 Questions · September 2026
BIO 340 Holechek Exam 3 Questions & Answers 2026/2027 | Arizona State University | Comprehensive Review (Rationales) - Practice Questions Page 0
, Topics Covered
Section 1: Molecular Biology Techniques Q 1-25
Questions covering molecular Biology Techniques concepts.
Section 2: Genetic Transfer and Resistance Q 26-33
Questions covering genetic Transfer and Resistance concepts.
Section 3: Genetic Testing and Applications Q 34-41
Questions covering genetic Testing and Applications concepts.
Section 4: Genomics and Human Genetics Q 42-53
Questions covering genomics and Human Genetics concepts.
Questions
QUESTION 1 OF 53
PCR
Correct Answer: This technique uses an extremophile in order to replicate DNA quickly.
Rationale: Polymerase Chain Reaction (PCR) relies on thermostable DNA polymerases, such as Taq polymerase
derived from the thermophilic bacterium *Thermus aquaticus*, to withstand the high temperatures required for DNA
denaturation during the cycling process. This heat resistance allows for repeated cycles of denaturation, annealing,
and extension, enabling rapid amplification of specific DNA sequences. The use of such extremophile enzymes is
fundamental to the efficiency and speed of PCR. This aligns with This technique uses an extremophile in order to
replicate DNA quickly..
QUESTION 2 OF 53
denaturation
Correct Answer: The first thing that happens to DNA during the PCR process is ____?
Rationale: During the initial step of Polymerase Chain Reaction (PCR), the double-stranded DNA template is heated
to a high temperature, typically between 94-98°C. This high temperature breaks the hydrogen bonds holding the two
complementary strands together, causing them to separate into single strands. This process is known as denaturation.
This aligns with The first thing that happens to DNA during the PCR process is ____?.
QUESTION 3 OF 53
primer annealing
Correct Answer: The second thing that happens during the PCR process is ____?
Rationale: Primer annealing is the step in Polymerase Chain Reaction (PCR) where short DNA sequences, the
primers, bind to complementary regions on the single-stranded template DNA. This binding occurs after denaturation,
where the DNA is heated to separate strands, and before extension, where DNA polymerase synthesizes new strands.
This precise binding allows for targeted amplification of specific DNA segments. This aligns with The second thing that
happens during the PCR process is ____?.
BIO 340 Holechek Exam 3 Questions & Answers 2026/2027 | Arizona State University | Comprehensive Review (Rationales) - Practice Questions Page 0
, QUESTION 4 OF 53
primer annealing
Correct Answer: phase in PCR during which a primer binds to a template strand
Rationale: Primer annealing is a critical step in the polymerase chain reaction (PCR) process. During this phase,
short, synthetic DNA sequences known as primers bind specifically to complementary regions on the denatured
template DNA strands. This binding is essential for DNA polymerase to initiate DNA synthesis and amplify the target
sequence. This aligns with phase in PCR during which a primer binds to a template strand.
QUESTION 5 OF 53
extension
Correct Answer: The final step of the PCR process is termed ____?
Rationale: The final step of the PCR process is termed ____?, after denaturation and annealing, the DNA
polymerase synthesizes new DNA strands. This synthesis step, where the enzyme extends the primer along the
template, is called the extension or elongation phase. Therefore, extension is the final step of the PCR process.
QUESTION 6 OF 53
negative
Correct Answer: what type of electric charge does DNA have?
Rationale: DNA possesses a negative electric charge due to the phosphate groups in its sugar-phosphate backbone.
These phosphate groups are deprotonated at physiological pH, leaving them with a net negative charge. This aligns
with what type of electric charge does DNA have?.
QUESTION 7 OF 53
size
Correct Answer: Other than charge what is a crucial component of DNA during gel electrophoresis?
Rationale: Other than charge what is a crucial component of DNA during gel electrophoresis?, DNA fragments
migrate through the porous gel matrix. While charge (due to the phosphate backbone) dictates the direction of
migration towards the positive electrode, the *size* of the DNA fragment determines its speed of movement. Smaller
fragments navigate the gel matrix more easily and thus travel further than larger fragments in a given amount of
time.
QUESTION 8 OF 53
Probes
Correct Answer: Short DNA fragments that can be stained with something such as a radioactive dye in
order to further understand DNA are called
Rationale: Short DNA fragments that can be stained with something such as a radioactive dye in order to further
understand DNA are called, labeled nucleic acid sequences used in molecular biology techniques like Southern blotting
or in situ hybridization to detect specific DNA or RNA sequences. The radioactive dye or other label allows for
visualization and identification of the target sequence within a larger sample. Therefore, DNA fragments stained for
identification are correctly identified as probes.
BIO 340 Holechek Exam 3 Questions & Answers 2026/2027 | Arizona State University | Comprehensive Review (Rationales) - Practice Questions Page 0
