WGU 785 COMMUNITY &
PUBLIC HEALTH NURSING
FINAL EXAM 2026/202 | Latest
Complete Solution | Pass
Section I: Protein Structure & Function (Questions 1-20)
Q1: Which level of protein structure is disrupted through the hydrolysis of
peptide bonds?
• A) Quaternary
• B) Tertiary
• C) Secondary
• D) Primary
Correct ,,,ANSWER,,,: D) Primary
Rationale: The primary structure of a protein is the linear sequence of amino acids
held together by covalent peptide bonds. Hydrolysis of peptide bonds breaks these
covalent linkages, destroying the primary structure. Secondary, tertiary, and
quaternary structures are dependent on non-covalent interactions (hydrogen bonds,
hydrophobic interactions, ionic bonds) and disulfide bridges, but these higher-order
structures cannot exist without an intact primary sequence.
,Q2: A mutation in the beta-hemoglobin gene results in replacement of
glutamate (negatively charged) at position 6 with valine (non-polar), leading
to sickle cell anemia. If the gene were edited to replace valine with a different
amino acid, which replacement would have the best clinical outcome?
• A) Leucine (non-polar, hydrophobic)
• B) Aspartate (negatively charged, polar)
• C) Alanine (non-polar, hydrophobic)
• D) Glycine (non-polar, hydrophobic)
Correct ,,,ANSWER,,,: B) Aspartate (negatively charged, polar)
Rationale: The original healthy amino acid is glutamate, which is negatively
charged and polar. The pathologic mutation substitutes valine, a non-polar,
hydrophobic amino acid, creating a hydrophobic "sticky" patch causing
aggregation and sickling. To restore normal function, the replacement should most
closely resemble glutamate. Aspartate is also negatively charged and polar, making
it the best theoretical replacement.
Q3: Secondary, tertiary, and quaternary levels of protein structure can all be
impacted by exposing a protein to which treatment?
• A) Change of a hydrophobic amino acid to a different hydrophobic amino
acid
• B) Addition of a reducing agent
• C) Placement of the protein in a solution with a low pH
• D) Increase in the concentration of the protein in solution
,Correct ,,,ANSWER,,,: C) Placement of the protein in a solution with a low
pH
Rationale: Changes in pH disrupt hydrogen bonds and ionic bonds throughout
protein structures. Hydrogen bonds in the polypeptide backbone maintain
secondary structure (alpha helices and beta sheets). Hydrogen bonds and ionic
bonds between amino acid side chains maintain tertiary structure. Quaternary
structure, involving interactions between multiple polypeptide subunits, also relies
on these same non-covalent forces.
Q4: An increase in beta-pleated sheet structure in some brain proteins can
lead to increased amyloid deposit formation, characteristic of some
neurodegenerative diseases. What is the primary biochemical process that
follows this increase?
• A) An increase in glycogen formation in the brain cells
• B) Aggregation of the proteins in the brain
• C) Secretion of glucagon, leading to excessive ketogenesis
• D) An increase in anaerobic metabolism of glucose in the brain
Correct ,,,ANSWER,,,: B) Aggregation of the proteins in the brain
Rationale: This question describes changes in protein structure. Aggregation
occurs when proteins clump together inappropriately, causing plaques like amyloid
deposits to form. In Alzheimer's disease, protein misfolding is caused by
intracellular tangles and extracellular plaques (senile plaques) due to abnormal
protein aggregation.
, Q5: What are the 4 levels of protein structure?
• A) Linear, spiral, folded, grouped
• B) Primary, secondary, tertiary, quaternary
• C) Alpha, beta, gamma, delta
• D) Monomer, dimer, trimer, tetramer
Correct ,,,ANSWER,,,: B) Primary, secondary, tertiary, quaternary
Rationale: Primary structure is the chain of amino acids held by PEPTIDE bonds
(covalent, very strong, does not denature). Secondary structure involves alpha
helices and beta sheets stabilized by HYDROGEN bonds (denatured by salt and
pH change). Tertiary structure involves side chain (R group) interactions (affected
by high temp, salt, pH change, reducing agents). Quaternary structure involves
more than one polypeptide (affected by increased temperature).
Q6: What structure would be unaffected by complete denaturation of a multi-
subunit protein?
• A) Secondary structure
• B) Tertiary structure
• C) Quaternary structure
• D) Primary structure
Correct ,,,ANSWER,,,: D) Primary structure
Rationale: Peptide bonds are strong and covalent. The primary structure is located
at the backbone and does NOT denature. Denaturation disrupts secondary, tertiary,
and quaternary structures by breaking hydrogen bonds and hydrophobic
interactions, but the primary sequence remains intact.
PUBLIC HEALTH NURSING
FINAL EXAM 2026/202 | Latest
Complete Solution | Pass
Section I: Protein Structure & Function (Questions 1-20)
Q1: Which level of protein structure is disrupted through the hydrolysis of
peptide bonds?
• A) Quaternary
• B) Tertiary
• C) Secondary
• D) Primary
Correct ,,,ANSWER,,,: D) Primary
Rationale: The primary structure of a protein is the linear sequence of amino acids
held together by covalent peptide bonds. Hydrolysis of peptide bonds breaks these
covalent linkages, destroying the primary structure. Secondary, tertiary, and
quaternary structures are dependent on non-covalent interactions (hydrogen bonds,
hydrophobic interactions, ionic bonds) and disulfide bridges, but these higher-order
structures cannot exist without an intact primary sequence.
,Q2: A mutation in the beta-hemoglobin gene results in replacement of
glutamate (negatively charged) at position 6 with valine (non-polar), leading
to sickle cell anemia. If the gene were edited to replace valine with a different
amino acid, which replacement would have the best clinical outcome?
• A) Leucine (non-polar, hydrophobic)
• B) Aspartate (negatively charged, polar)
• C) Alanine (non-polar, hydrophobic)
• D) Glycine (non-polar, hydrophobic)
Correct ,,,ANSWER,,,: B) Aspartate (negatively charged, polar)
Rationale: The original healthy amino acid is glutamate, which is negatively
charged and polar. The pathologic mutation substitutes valine, a non-polar,
hydrophobic amino acid, creating a hydrophobic "sticky" patch causing
aggregation and sickling. To restore normal function, the replacement should most
closely resemble glutamate. Aspartate is also negatively charged and polar, making
it the best theoretical replacement.
Q3: Secondary, tertiary, and quaternary levels of protein structure can all be
impacted by exposing a protein to which treatment?
• A) Change of a hydrophobic amino acid to a different hydrophobic amino
acid
• B) Addition of a reducing agent
• C) Placement of the protein in a solution with a low pH
• D) Increase in the concentration of the protein in solution
,Correct ,,,ANSWER,,,: C) Placement of the protein in a solution with a low
pH
Rationale: Changes in pH disrupt hydrogen bonds and ionic bonds throughout
protein structures. Hydrogen bonds in the polypeptide backbone maintain
secondary structure (alpha helices and beta sheets). Hydrogen bonds and ionic
bonds between amino acid side chains maintain tertiary structure. Quaternary
structure, involving interactions between multiple polypeptide subunits, also relies
on these same non-covalent forces.
Q4: An increase in beta-pleated sheet structure in some brain proteins can
lead to increased amyloid deposit formation, characteristic of some
neurodegenerative diseases. What is the primary biochemical process that
follows this increase?
• A) An increase in glycogen formation in the brain cells
• B) Aggregation of the proteins in the brain
• C) Secretion of glucagon, leading to excessive ketogenesis
• D) An increase in anaerobic metabolism of glucose in the brain
Correct ,,,ANSWER,,,: B) Aggregation of the proteins in the brain
Rationale: This question describes changes in protein structure. Aggregation
occurs when proteins clump together inappropriately, causing plaques like amyloid
deposits to form. In Alzheimer's disease, protein misfolding is caused by
intracellular tangles and extracellular plaques (senile plaques) due to abnormal
protein aggregation.
, Q5: What are the 4 levels of protein structure?
• A) Linear, spiral, folded, grouped
• B) Primary, secondary, tertiary, quaternary
• C) Alpha, beta, gamma, delta
• D) Monomer, dimer, trimer, tetramer
Correct ,,,ANSWER,,,: B) Primary, secondary, tertiary, quaternary
Rationale: Primary structure is the chain of amino acids held by PEPTIDE bonds
(covalent, very strong, does not denature). Secondary structure involves alpha
helices and beta sheets stabilized by HYDROGEN bonds (denatured by salt and
pH change). Tertiary structure involves side chain (R group) interactions (affected
by high temp, salt, pH change, reducing agents). Quaternary structure involves
more than one polypeptide (affected by increased temperature).
Q6: What structure would be unaffected by complete denaturation of a multi-
subunit protein?
• A) Secondary structure
• B) Tertiary structure
• C) Quaternary structure
• D) Primary structure
Correct ,,,ANSWER,,,: D) Primary structure
Rationale: Peptide bonds are strong and covalent. The primary structure is located
at the backbone and does NOT denature. Denaturation disrupts secondary, tertiary,
and quaternary structures by breaking hydrogen bonds and hydrophobic
interactions, but the primary sequence remains intact.
