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WGU C785 BIOCHEMISTRY EXAM OBJECTIVE
ASSESSMENT COMPLETE 550 QUESTIONS AND
CORRECT DETAILED ANSWERS LATEST UPDATE
THIS YEAR - JUST RELEASED
WGU C785 Biochemistry Exam QUESTION: Given the following amino acid structure, what is the strongest intermolecular force it would participate in to stabilize a protein structure?
Ionic bond
Disulfide bond
Hydrogen bond
Hydrophobic interaction - ANSWER-Hydrophobic interaction
The amino acid pictured only has CH groups in its side chain, and therefore is non-polar. Non- polar amino acids make hydrophobic interactions. 1 / 4
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QUESTION: Which change would most likely result in a permanent modification of an expressed protein's function?
An increase in the pH of a solution in which a protein is dissolved from 6.5 to 8.0, when it is known that the protein has an optimal activity of pH 7.8
A mutation of the gene for a protein that leads to the substitution of a hydrophobic amino acid with a nonpolar amino acid
A mutation of the gene for a protein that leads to the substitution of a nonpolar amino acid with a charged amino acid
The mutation of a gene for an enzyme involved in protein synthesis following exposure to X- rays, causing the protein not to be synthesized - ANSWER-A mutation of the gene for a protein that leads to the substitution of a nonpolar amino acid with a charged amino acid.
The mutation of nonpolar amino acid to a charged amino acid will disrupt the original hydrophobic interaction, permanently changing the function of the protein.
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3 QUESTION: Which property of enzymes is illustrated in the final step of the enzymatic cycle?
Enzymes are specific.
Enzymes increase the reaction rate for a reaction.
Enzymes are reusable.
Enzymes lower the activation energy for a reaction. - ANSWER-Enzymes are reusable.Which level of protein structure is disrupted through the hydrolysis of peptide bonds?
Quaternary
Tertiary
Primary
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4 Secondary - ANSWER-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.
QUESTION: 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.
QUESTION: Secondary, tertiary, and quaternary levels of protein structure can all be impacted by exposing a protein to which treatment?
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