WGU BIOCHEMISTRY 785 ACTUAL TEST
PAPER 2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◉A mutation in the beta-hemoglobin gene, which results in the
replacement of the amino acid glutamate in position 6 with the
amino acid valine, leads to the development of sickle cell anemia.
The structures of glutamate and valine are shown below.
If the beta hemoglobin gene in a patient with sickle-cell anemia were
to be edited so that the valine in position 6 was replaced with a
different amino acid, which replacement for valine would be
expected to have the best clinical outcome, in theory, for the patient?
(Assume the valine can potentially be replaced with any amino acid
other than glutamate.). Answer: The original amino acid in a healthy
patient is glutamate, which is negatively charged. The mutated
amino acid is valine, which is non-polar. Valine is causing sickle cell
anemia. The best amino acid to replace valine so that the patient is
healthy again would be the one most like glutamate, so any
negatively charged amino acid.
◉Secondary, tertiary, and quaternary levels of protein structure can
all be impacted by exposing a protein to which treatment?
,Change of a hydrophobic amino acid to a different hydrophobic
amino acid
Addition of a reducing agent
Placement of the protein in a solution with a low pH
Increase in the concentration of the protein in solution. Answer:
Placement of the protein in a solution with a low pH
Changes in pH affect hydrogen bonds and ionic bonds. Hydrogen
bonds in the backbone of amino acids occur in secondary structure,
and both hydrogen bonds and ionic bonds occur in the side chains of
amino acids in tertiary structure.
◉An increase in beta-pleated sheet structure in some brain proteins
can lead to an increase in amyloid deposit formation, characteristic
of some neurodegenerative diseases. What is the primary
biochemical process that follows the increase in beta-pleated sheet
structure that leads to the development of the amyloid deposits?
An increase in glycogen formation in the brain cells
Aggregation of the proteins in the brain
,Secretion of glucagon, leading to excessive ketogenesis
An increase in anaerobic metabolism of glucose in the brain.
Answer: Aggregation of the proteins in the brain
This question is describing changes in protein structure.
Aggregation occurs when proteins clump together inappropriately,
causing plaques like amyloid deposits to accumulate.
◉Which level of protein structure is determined by the sequence of
amino acids?
Secondary structure
Quaternary structure
Tertiary structure
Primary structure. Answer: Primary structure
The primary structure of a protein is simply the sequence of amino
acids held together by peptide bonds.
, ◉Which force is most influential in determining the secondary
structure of a protein?
Hydrophobic effect
Disulfide bonding
Hydrogen bonding
Electrostatic interactions. Answer: Hydrogen bonding
The secondary structure of a protein is built by hydrogen bonds
between the carboxyl groups and amino groups on the backbones of
the amino acids.
◉Which amino acid would most likely participate in hydrogen
bonds?. Answer: Amino Acid structure 4
This is a polar, uncharged amino acid due to the OH group on the
side chain. Polar, uncharged amino acids containing oxygen or NH
groups make hydrogen bonds.
PAPER 2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◉A mutation in the beta-hemoglobin gene, which results in the
replacement of the amino acid glutamate in position 6 with the
amino acid valine, leads to the development of sickle cell anemia.
The structures of glutamate and valine are shown below.
If the beta hemoglobin gene in a patient with sickle-cell anemia were
to be edited so that the valine in position 6 was replaced with a
different amino acid, which replacement for valine would be
expected to have the best clinical outcome, in theory, for the patient?
(Assume the valine can potentially be replaced with any amino acid
other than glutamate.). Answer: The original amino acid in a healthy
patient is glutamate, which is negatively charged. The mutated
amino acid is valine, which is non-polar. Valine is causing sickle cell
anemia. The best amino acid to replace valine so that the patient is
healthy again would be the one most like glutamate, so any
negatively charged amino acid.
◉Secondary, tertiary, and quaternary levels of protein structure can
all be impacted by exposing a protein to which treatment?
,Change of a hydrophobic amino acid to a different hydrophobic
amino acid
Addition of a reducing agent
Placement of the protein in a solution with a low pH
Increase in the concentration of the protein in solution. Answer:
Placement of the protein in a solution with a low pH
Changes in pH affect hydrogen bonds and ionic bonds. Hydrogen
bonds in the backbone of amino acids occur in secondary structure,
and both hydrogen bonds and ionic bonds occur in the side chains of
amino acids in tertiary structure.
◉An increase in beta-pleated sheet structure in some brain proteins
can lead to an increase in amyloid deposit formation, characteristic
of some neurodegenerative diseases. What is the primary
biochemical process that follows the increase in beta-pleated sheet
structure that leads to the development of the amyloid deposits?
An increase in glycogen formation in the brain cells
Aggregation of the proteins in the brain
,Secretion of glucagon, leading to excessive ketogenesis
An increase in anaerobic metabolism of glucose in the brain.
Answer: Aggregation of the proteins in the brain
This question is describing changes in protein structure.
Aggregation occurs when proteins clump together inappropriately,
causing plaques like amyloid deposits to accumulate.
◉Which level of protein structure is determined by the sequence of
amino acids?
Secondary structure
Quaternary structure
Tertiary structure
Primary structure. Answer: Primary structure
The primary structure of a protein is simply the sequence of amino
acids held together by peptide bonds.
, ◉Which force is most influential in determining the secondary
structure of a protein?
Hydrophobic effect
Disulfide bonding
Hydrogen bonding
Electrostatic interactions. Answer: Hydrogen bonding
The secondary structure of a protein is built by hydrogen bonds
between the carboxyl groups and amino groups on the backbones of
the amino acids.
◉Which amino acid would most likely participate in hydrogen
bonds?. Answer: Amino Acid structure 4
This is a polar, uncharged amino acid due to the OH group on the
side chain. Polar, uncharged amino acids containing oxygen or NH
groups make hydrogen bonds.
