UNIT 1 - Quizzes and Exam, UNE medical biochemistry Unit 1 Test Correctly Answered To Score A+

UNIT 1 - Quizzes and Exam, UNE medical biochemistry Unit 1 Test Correctly Answered To Score A+ Which of the following amino acid would not be commonly found in the middle of a an α-helical domain? 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 Increase in 2,3 bisphosphoglycerate (BPG) 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? Amylase Which of the following is the best description of primary protein structure? 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? Lyase Which of the following amino acid would not be commonly found in the middle of a an α-helical domain? 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 An arrangement of β-strands connected by α-helixes α helices and β sheets are primarily stabilized by which of the following interactions? 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: 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? 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? 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 amylase Hemoglobin binds oxygen with a greater affinity in the: 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? Folding of the secondary structures α-helices and β-sheets are primarily stabilized by which of the following interactions Hydrogen bonding Movement of ammonia from an amino acid to an alpha-keto acid involves a family of enzymes best categorized as: a) transferases b) ligases c) lyases d) isomerases transferases