6. Which of the following statements are accurate?
A. In an average, healthy human, the partial pressure ofcarbon dioxide is usually higher in the blood in systemic veinsthan the alveoli
B. In an average, healthy human, the partial pressure ofoxygen is usually higher in the systemic veins than thealveoli
C. In average, healthy human, the partial pressure of oxygenis usually higher in the systemic arteries than in the bodytissues
D. Generally speaking, gases will diffuse down their pressuregradient
E. In an average, healthy human, the partial pressure ofcarbon dioxide is usually higher in the body tissues than thesystemic arteries.
7. Which of the following statements are accurate?
A. Humans bring air into their lungs by generating a positivepressure (higher pressure relative to the atmosphere)
B. When the diaphragm contracts it becomes dome-shaped andcauses the lung to decrease in volume which decreases the pressureof air in the lungs.
C. In a close chamber (such as the lungs), As the volume of agas increases the pressure decreases
D. The diaphragm is the primary breathing muscles inhumans
E. In human lungs, new air mixes with air in the lungsalready. This decreases the efficiency of ventilation
