Final answer:
The statement about ventricles having one-way valves at their entrances and exits to ensure blood flows in the proper direction is true. The heart relies on a coordinated contraction of atria and ventricles along with these valves to maintain unidirectional blood flow.
Step-by-step explanation:
The statement that 'ventricles have one-way valves at their entrances and exits so that blood goes in the proper direction as the heart pumps' is true.
The human heart consists of four chambers, with two atria on top and two ventricles below. Blood enters the heart at the atria, which contract and push it into the ventricles. The heart's function relies on a coordinated cycle where the atria contract (atrial systole), followed by the relaxation (atrial diastole) while the ventricles fill with blood. Then, the ventricles contract, pushing blood through the body.
Essential to this process are the heart valves that ensure unidirectional blood flow. The atrioventricular valves, namely the tricuspid on the right and the mitral (or bicuspid) on the left, regulate blood flow from the atria to the ventricles. When the ventricles contract, the semilunar valves (the pulmonary valve on the right and the aortic valve on the left) open, allowing blood to be ejected into the pulmonary artery and aorta, respectively, and closing to prevent backflow into the ventricles.