What happens during systole?

What happens during systole?

• A. Contraction of a heart chamber.
• B. Relaxation of a heart chamber.
• C. Blood flowing into the veins.
• D. Valve leakage.

Answer: (A)

During systole, the heart muscle contracts to eject blood from the chambers. When the ventricles contract, pressure rises and blood is pushed into the aorta and pulmonary artery, while the atrioventricular valves close to prevent backflow. Atrial contraction and filling occur mainly near the end of diastole, not during systole. Relaxation of a chamber is diastole, not systole. Blood flowing into the veins reflects venous return to the heart, not the pumping action of systole. Valve leakage implies regurgitation, an abnormal condition, not the normal systolic pumping event.

During systole, the heart muscle contracts to eject blood from the chambers. When the ventricles contract, pressure rises and blood is pushed into the aorta and pulmonary artery, while the atrioventricular valves close to prevent backflow. Atrial contraction and filling occur mainly near the end of diastole, not during systole. Relaxation of a chamber is diastole, not systole. Blood flowing into the veins reflects venous return to the heart, not the pumping action of systole. Valve leakage implies regurgitation, an abnormal condition, not the normal systolic pumping event.