Final answer:
The heart's atrioventricular valves, including the tricuspid and bicuspid (mitral) valves, prevent backflow from the ventricles to the atria. The pulmonic and aortic semilunar valves stop blood from flowing back into the ventricles from the arteries. These valves ensure the one-way flow of blood necessary for efficient circulation.
Step-by-step explanation:
Valves of the Heart
The human heart consists of four chambers, divided into the upper atria and the lower ventricles. Atrioventricular valves are crucial for preventing the backflow of blood from the ventricles to the atria during contraction. The right side of the heart has the tricuspid valve, while the left side contains the bicuspid valve or mitral valve. Additionally, the semilunar valves located at the exits of the ventricles, namely the pulmonic valve and aortic valve, ensure blood does not return to the ventricles from the pulmonary trunk and aorta, respectively.
The valves work in conjunction with the cardiac skeleton to support and maintain the unidirectional flow of blood through the heart, crucial for efficient circulation. Double circulation ensures separation of oxygenated and deoxygenated blood, which is fundamental for mammalian cardiovascular systems. The atrioventricular septum provides structural support for these valves.