Biochem C785 - WGU - Module 3 - All Questions 2022/2023

Biochem C785 - WGU - Module 3 - All Questions Hb (hemoglobin) binds to CO (carbon monoxide) with a higher affinity than oxygen and stabilizes the R (relaxed) state Correct Answer: True When hemoglobin changes from the T to the R, it has a high affinity for oxygen Correct Answer: True When hemoglobin changes from the R to T, it has a low affinity for oxygen Correct Answer: True Cooperatively refers to Correct Answer: structural changes that increases the affinity for oxygen in hemoglobin When the oxygen concentration is high, the heme shape is planar. When the oxygen concentration is low, the heme shape is bent shape. Correct Answer: True The Bohr effect is a relationship between hemoglobin's oxygen binding behavior in conjunction with the pH of the surroundings. When the pH is low, hemoglobin has low affinity for oxygen and releases oxygen Correct Answer: True Bohr effect is a relationship between hemoglobin's oxygen binding behavior in conjunction with the pH of the surroundings. When the pH is high, hemoglobin has high affinity for oxygen and binds oxygen. Correct Answer: True Relative to the lungs, the pH in the peripheral tissues is lower, because the CO2 generated by metabolism is converted to bicarbonate, which releases proton (H+) Correct Answer: True The Bohr effect is a relationship between hemoglobin's oxygen binding behavior in conjunction with the pH of the surroundings. When the H+ ion concentration increases, the pH of the solution decreases. Correct Answer: True Myoglobin stores oxygen, whereas hemoglobin transports oxygen. Myoglobin has a higher affinity for oxygen compared to hemoglobin Correct Answer: True Hemoglobin is an oxygen transport protein, whereas myoglobin is an oxygen storage protein. They exhibit different binding curves when plotted on a graph with total partial pressure of the oxygen (xaxis) plotted against the percentage saturation of hemoglobin (y-axis). What pattern of binding curves do these proteins exhibit? Correct Answer: Hemoglobin has a sigmoidal curve whereas the myoglobin has a hyperbolic curve. Hemoglobin and myoglobin proteins bind to molecular oxygen. However, the protein part of the hemoglobin does not bind directly to the oxygen. Instead a specific atom helps bind the oxygen - Correct Answer: Iron The symptoms of sickle cell anemia are primarily because red blood cells are misshaped, due to Correct Answer: a mutation in the beta hemoglobin gene which leads to the insertion of valine into the hydrophobic patches on deoxygenated hemoglobin Relative to the peripheral tissues, the pH in lungs is higher, because Correct Answer: the protons (H+) that were combined with hemoglobin quickly bind to bicarbonate (HCO3-) to form CO2; the CO2 is then exhaled Why is carbon monoxide poisonous? Correct Answer: it binds hemoglobin 200 times better than oxygen BPG stabilizes the T (tense) states of hemoglobin Correct Answer: True Even though the amino acids sequence between subunits of hemoglobin and myoglobin are not exactly the same, there are other similarities between the two proteins. Which level of protein structure is not found in both molecules? Correct Answer: Quarternary In the deoxygenated state the heme is bent, where as in the oxygenated state, the heme is planar. Correct Answer: True Fetal hemoglobin binds to oxygen tightly at lower oxygen concentrations since its R state is the preferred structure. Correct Answer: True When blood pH is low, the heme is in bent shape. When the blood pH is high, the heme is in planar shape. Correct Answer: True In a firefighter who is brought to the emergency room after entering a burning building, the planar confirmation of the heme group in hemoglobin is preferred Correct Answer: True Structurally, hemoglobin can bind 4 molecules of oxygen, all of which could potentially be replaced by carbon monoxide. Correct Answer: True CONTINUES...