The heart is a hollow organ with how many chambers?

The heart is a hollow organ with how many chambers?

• A. Four
• B. Two
• C. Three
• D. Five

Answer: (A)

The heart is organized as a four-chamber pump: two atria and two ventricles. The atria receive blood returning to the heart, while the ventricles pump blood out. This arrangement keeps the two main blood routes separate—the right side handles deoxygenated blood to the lungs (pulmonary circuit) and the left side handles oxygenated blood to the body (systemic circuit). Valves between the chambers and at the exits enforce one-way flow, preventing backflow and allowing the heart to function as a coordinated double pump. Some animals have fewer chambers, but in humans the four-chamber structure is essential for efficient circulation.

The heart is organized as a four-chamber pump: two atria and two ventricles. The atria receive blood returning to the heart, while the ventricles pump blood out. This arrangement keeps the two main blood routes separate—the right side handles deoxygenated blood to the lungs (pulmonary circuit) and the left side handles oxygenated blood to the body (systemic circuit). Valves between the chambers and at the exits enforce one-way flow, preventing backflow and allowing the heart to function as a coordinated double pump. Some animals have fewer chambers, but in humans the four-chamber structure is essential for efficient circulation.