Final answer:
The heart chamber with the highest oxygen consumption due to its intense workload is the left ventricle. It is responsible for pumping oxygen-rich blood throughout the body, requiring strong contractions and, consequently, more oxygen.
Step-by-step explanation:
The heart chamber whose myocardium consumes the most oxygen is D) Left ventricle. The left ventricle has the thickest myocardium because it needs to pump oxygen-rich blood out of the heart to the rest of the body with enough force to overcome systemic arterial pressure. This high workload demands a high oxygen consumption to maintain efficient muscle contraction.
Regarding the circulation of blood and the role of the heart's chambers:
- The right atrium receives oxygen-poor blood from the body.
- The left atrium receives oxygen-rich blood from the lungs.
- The right ventricle pumps oxygen-poor blood toward the lungs for oxygenation.
- The left ventricle pumps oxygen-rich blood to the systemic circuit, i.e., to the rest of the body.