WGU Biochemistry PA Comprehensive
Questions (Frequently Tested) with
Verified Answers Graded A+
What is the complementary sequence for the following DNA sequence? 5' - GCC ATC TCG AAT -
3' - Answer: 5' - ATT CGA GAT GGC - 3'
Assuming 100% reaction efficiency, how many DNA copies are created after the completion of
four complete PCR cycles? - Answer: 16
What is the function of DNA polymerase in the process of PCR? - Answer: It recognizes the
primers and uses the available dNTPs to replicate the template DNA sequence.
What are possible blood types of the parents of a patient with blood type AB? - Answer: A and B
Studies have shown that increased expression of two genes called SIRT1 and SIRT2 is associated
with chronic exposure to cocaine and contributes to drug addiction. What difference in the
regions of the SIRT1 and SIRT2 genes in people addicted to cocaine increases their expression? -
Answer: The nucleosomes become more widely spaced.
Mice with low levels of agouti gene expression tend to have yellow fur and are obese, while
mice with higher levels of expression are brown and of normal weight. Studies show that
expression of the agouti gene in mice can be controlled by epigenetics. What scenario describes
epigenetic regulation of the agouti gene? - Answer: Mother mice fed methyl-rich diets during
pregnancy give birth to offspring with decreased agouti gene expression compared to those fed
a methyl-poor diet.
Oxidative damage to DNA can often result in the alteration of a single nucleotide. Which DNA
repair mechanism would repair this type of damage? - Answer: The mutation rate of all other
genes is higher due to failure to repair.
, Which reaction is responsible for the formation of polypeptides? - Answer: Dehydration
Which term describes the order of amino acids in a peptide chain? - Answer: Primary structure
When using heat to denature a protein, which force is the first to be disrupted as temperature
increases? - Answer: Hydrophobic interactions
A commonly used technique for protein denaturation is adding an acid or a base to dramatically
change the pH. Which force is most impacted by this change in pH? - Answer: Ionic bonds
An active elderly patient is becoming frequently disoriented, having trouble recalling her daily
routine, and becoming aggravated easily. She forgets words and places and has difficulty
recognizing her children. Which biochemical event is responsible for this patient's behavior? -
Answer: Protein aggregation
In which situation would altering a protein structure lead to a disease state? - Answer: A
mutation in aconitase blocks an essential step in aerobic metabolism
Frying an egg changes the egg white from a clear liquid to an opaque solid. Which molecular
change in the albumin protein causes this change in appearance? - Answer: Hydrophobic
interactions form between denatured egg white proteins.
What is the driving mechanism of plaque formation in prion diseases? - Answer: Propagation of
misfolding from one protein to another
Which feature of a protein made of a single polypeptide chain is most directly responsible for its
function? - Answer: Three-dimensional structure
Questions (Frequently Tested) with
Verified Answers Graded A+
What is the complementary sequence for the following DNA sequence? 5' - GCC ATC TCG AAT -
3' - Answer: 5' - ATT CGA GAT GGC - 3'
Assuming 100% reaction efficiency, how many DNA copies are created after the completion of
four complete PCR cycles? - Answer: 16
What is the function of DNA polymerase in the process of PCR? - Answer: It recognizes the
primers and uses the available dNTPs to replicate the template DNA sequence.
What are possible blood types of the parents of a patient with blood type AB? - Answer: A and B
Studies have shown that increased expression of two genes called SIRT1 and SIRT2 is associated
with chronic exposure to cocaine and contributes to drug addiction. What difference in the
regions of the SIRT1 and SIRT2 genes in people addicted to cocaine increases their expression? -
Answer: The nucleosomes become more widely spaced.
Mice with low levels of agouti gene expression tend to have yellow fur and are obese, while
mice with higher levels of expression are brown and of normal weight. Studies show that
expression of the agouti gene in mice can be controlled by epigenetics. What scenario describes
epigenetic regulation of the agouti gene? - Answer: Mother mice fed methyl-rich diets during
pregnancy give birth to offspring with decreased agouti gene expression compared to those fed
a methyl-poor diet.
Oxidative damage to DNA can often result in the alteration of a single nucleotide. Which DNA
repair mechanism would repair this type of damage? - Answer: The mutation rate of all other
genes is higher due to failure to repair.
, Which reaction is responsible for the formation of polypeptides? - Answer: Dehydration
Which term describes the order of amino acids in a peptide chain? - Answer: Primary structure
When using heat to denature a protein, which force is the first to be disrupted as temperature
increases? - Answer: Hydrophobic interactions
A commonly used technique for protein denaturation is adding an acid or a base to dramatically
change the pH. Which force is most impacted by this change in pH? - Answer: Ionic bonds
An active elderly patient is becoming frequently disoriented, having trouble recalling her daily
routine, and becoming aggravated easily. She forgets words and places and has difficulty
recognizing her children. Which biochemical event is responsible for this patient's behavior? -
Answer: Protein aggregation
In which situation would altering a protein structure lead to a disease state? - Answer: A
mutation in aconitase blocks an essential step in aerobic metabolism
Frying an egg changes the egg white from a clear liquid to an opaque solid. Which molecular
change in the albumin protein causes this change in appearance? - Answer: Hydrophobic
interactions form between denatured egg white proteins.
What is the driving mechanism of plaque formation in prion diseases? - Answer: Propagation of
misfolding from one protein to another
Which feature of a protein made of a single polypeptide chain is most directly responsible for its
function? - Answer: Three-dimensional structure