WGU C785 Biochemistry Unit
Exam 2026 Questions and Answers
Which level of protein structure is disrupted through the hydrolysis of peptide
bonds?
Quaternary
Tertiary
Primary
Secondary - Correct answer-Primary
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,The primary structure of a protein is the sequence of amino acids held together by
peptide bonds. Peptide bonds are formed by dehydration reactions and disrupted by
hydrolysis.
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.) - Correct 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?
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,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 - Correct 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?
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, 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 - Correct 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
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Exam 2026 Questions and Answers
Which level of protein structure is disrupted through the hydrolysis of peptide
bonds?
Quaternary
Tertiary
Primary
Secondary - Correct answer-Primary
©COPYRIGHT 2025, ALL RIGHTS RESERVE 1
,The primary structure of a protein is the sequence of amino acids held together by
peptide bonds. Peptide bonds are formed by dehydration reactions and disrupted by
hydrolysis.
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.) - Correct 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?
©COPYRIGHT 2025, ALL RIGHTS RESERVE 2
,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 - Correct 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?
©COPYRIGHT 2025, ALL RIGHTS RESERVE 3
, 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 - Correct 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
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