What percentage of oxygen in the blood is transported by hemoglobin as oxyhemoglobin within red blood cells?

Which of the following correctly describes the sequence of excitation of heart muscle?

What causes an increase in ventilation?

Which is a principal structure of the ventilatory system?

Which is a definition of vital capacity?

The graph below represents lung volume. What is labelled X?

Which of the following are correct statements about the pulmonary and systemic circulatory systems?

I. Pulmonary circulation is driven from the right ventricle to drop off carbon dioxide at the lungs.

II. Systemic circulation brings back oxygen from the lungs for the rest of the body.

III. The vena cava is involved with the systemic circulatory system.

IV. Pulmonary circulation has lower blood pressure than the systemic system.

How does an increased erythrocyte level benefit an athlete?

Which describes the cardiac output of an athlete recovering from strenuous exercise?

Which four are principal structures of the ventilatory system?