WGU C785 Final Exam 2024 With All The Correct Answers
1. Which level of protein structure is disrupted through the hydrolysis of
peptide bonds?
Quaternary
Tertiary
Primary
Secondary: Primary
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.
,2. 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 clin-
ical outcome, in theory, for the patient? (Assume the valine can potentially
be replaced with any amino acid other than glutamate.): 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.
3. 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: 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.
4. 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 devel-
opment 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: 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