Which component is described as a muscular pump that pushes blood through the body's vessels?

Which component is described as a muscular pump that pushes blood through the body's vessels?

• A. Lungs
• B. Heart
• C. Stomach
• D. Kidneys

Answer: (B)

The heart is the muscular pump that pushes blood through the body's vessels. Its thick walls (the cardiac muscle) contract in a coordinated rhythm, sending blood into the arteries on each beat and maintaining the circulation needed to deliver oxygen and nutrients to tissues while returning deoxygenated blood to the lungs for re-oxygenation. The heart's two sides work in tandem: the left ventricle pumps oxygen-rich blood to the rest of the body, while the right ventricle sends blood to the lungs. Valves ensure blood moves in only one direction, preventing backflow. Lungs do gas exchange and receive blood from the heart, but they do not push blood through vessels. Stomach digests food, and kidneys filter and regulate fluids and wastes; neither acts as the main muscular pump for circulating blood.

The heart is the muscular pump that pushes blood through the body's vessels. Its thick walls (the cardiac muscle) contract in a coordinated rhythm, sending blood into the arteries on each beat and maintaining the circulation needed to deliver oxygen and nutrients to tissues while returning deoxygenated blood to the lungs for re-oxygenation. The heart's two sides work in tandem: the left ventricle pumps oxygen-rich blood to the rest of the body, while the right ventricle sends blood to the lungs. Valves ensure blood moves in only one direction, preventing backflow.

Lungs do gas exchange and receive blood from the heart, but they do not push blood through vessels. Stomach digests food, and kidneys filter and regulate fluids and wastes; neither acts as the main muscular pump for circulating blood.