EXAM LATEST VERSION 2025 QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED
ANSWERS) |ALREADY GRADED A
A 22-year old female presents to the emergency department with acute
abdominal pain. She indicates the pain came on rapidly in her mid-abdominal
region. She has vomited several times over the last 4 hours. A diagnosis of acute
pancreatitis is made and she is rushed to surgery. Elevation of which of the
following serum enzymes would be consistent with this diagnosis? - CORRECT
ANSWER-Amylase
Which of the following is the best description of primary protein structure? -
CORRECT ANSWER-A newly synthesized strand of amino acids
Cleavage of fructose 1, 6-bisphosphate to dihydroxyacetone and glyceraldehyde
3-phosphate is achieved by what class of enzymes? - CORRECT ANSWER-Lyase
Which of the following amino acid would not be commonly found in the middle of
a an α-helical domain? - CORRECT ANSWER-Proline
,Domains are common structural elements that retain a particular function within
the protein. Which of the following is an example of a protein domain?
a) a prosthetic group such as heme
b) irregular coils and loops
c) an arrangement of β-strands connected by α- helixes
d) a single α- helix - CORRECT ANSWER-An arrangement of β-strands connected
by α-helixes
α helices and β sheets are primarily stabilized by which of the following
interactions? - CORRECT ANSWER-hydrogen bonding
Hydrogen bonding is the primary stabilizing force in both secondary structures. In
alpha helices the hydrogen bond is between the carbonyl oxygen group from one
peptide bond and that amide hydrogen from a different peptide bond
approximately amide 4 resides down in the helix. In beta sheets, the hydrogen
bonding is between the carbonyl oxygen and the amide hydrogen from different
peptide strands.
Compare and contrast beta sheets and alpha helical formations. (Figure 7.3 vs.
7.5)
Phosphorylation of an amino acid changes the charge on the residue to: -
CORRECT ANSWER-Negative
,The addition of a phospho group will add a large negative moiety to the amino
acid and change the functionality of the protein.
Which of the following amino acid would not be commonly found in the middle of
a an α-helical domain? - CORRECT ANSWER-Proline.
It is considered a 'helix breaker' and would not be found in an alpha helix; all
other residues are nonpolar hydrophobic and could reside in a transmemebrane
domain.
Changes in the physiological variables listed below can alter the affinity of
hemoglobin for oxygen. Which of the following will lower the affinity of
hemoglobin for oxygen?
a) decrease in protons
b) increase in 2,3 bisphosphoglycerate (BPG)
c) increase in pH
d) decrease in CO2 - CORRECT ANSWER-Increase in 2,3 bisphosphoglycerate
(BPG)
Which of the following amino acid would not be commonly found in the middle of
a an α-helical domain? - CORRECT ANSWER-Proline
A 55-year old man is brought to the emergency room with a chief complaint of
chest pain and tingling in his left arm. Elevation of which of the following enzymes
in circulation would be most indicative of a myocardial infarction? - CORRECT
, ANSWER-Troponin
A 22-year-old female is diagnosed with acute pancreatitis. Elevation of which of
the following serum enzymes would be consistent with this diagnosis?
a) lactate dehydrogenase
b) amylase
c) troponin
d) creatine kinase - CORRECT ANSWER-amylase
Hemoglobin binds oxygen with a greater affinity in the: - CORRECT ANSWER-R-
State --- Hemoglobin binds oxygen with a greater affinity in the R state. As oxygen
binds each subunit, the affinity for oxygen increases; this is termed cooperative
binding.
A 19-year-old boy is diagnosed with Creutzfeldt-Jakob Disease which is caused by
the introduction of an amyloid fold in the disease-causing protein. The
introduction of this fold causes the protein to transition from a primarily α-helical
structure to an aggregate of mostly β-sheets. This change in protein structure
(leading to disease) is best attributed to changes in which of the following? -
CORRECT ANSWER-Folding of the secondary structures
α-helices and β-sheets are primarily stabilized by which of the following
interactions - CORRECT ANSWER-Hydrogen bonding