PRACTICE QUESTIONS

1. If 1 g of hemoglobin has an oxygen capacity of 1.36 mL of oxygen, what is the oxygen content of blood containing 10 g of hemoglobin when the blood Po₂ is 70 mm Hg?

a.

b. 9.5 mL/dL (vol⁰∕o)

c. 6.8 mL/dL (vol%)

d. 21 mL/dL (vol%)

e. Cannot be calculated from the information provided.

2. An increase in pH of blood will:

a. Shift the oxyhemoglobin dissociation curve to the right.

b. Decrease P₅₀.

c. Decrease the affinity of hemoglobin for oxygen.

d. Decrease the oxygen capacity of the blood.

e. Do all the above.

3. Which of the following decreases oxygen content but does not alter Pao₂ or percentage saturation of hemoglobin?

a. Ascent to an altitude of 3500 m

b. Polycythemia

c. Breathing 50% oxygen

d. Anemia

e. Development of a large right-to-left shunt

4. All the following shift the oxyhemoglobin dissociation curve to the right except:

a. An increase in pH

b. An increase in Pco₂

c. An increase in 2,3-DPG

d. An increase in temperature

5. Quantitatively, the most important form of carbon dioxide (CO₂) transport is:

a. HCO₃" produced in plasma

b. CO₂ dissolved in plasma

c. HCO₃" produced in the erythrocyte

d. CO₂ dissolved in the erythrocyte

e. CO₂ combined with plasma proteins

6. Oxygenation of hemoglobin in the lungs assists with the release of CO₂ from the blood because:

a. Oxygen combines with the -NH groups on hemo­globin and displaces CO₂ from Carbamino com­pounds.

b. Oxygen combines with HCO₃" and produces CO₂.

c. Oxygen facilitates the movement of chloride ions out of the erythrocyte.

d. Oxygen combines with hemoglobin, making it a better buffer, which retains H’.

e. Noneoftheabove.