The Heart and Blood Vessels
Your heart is divided into four chambers—two atria that collect returning blood and two ventricles that pump it out. The left side handles oxygenated blood (pushing it to your body) while the right side manages deoxygenated blood (sending it to your lungs). The left side is stronger since it needs to pump blood throughout your entire body.
Blood travels through three main types of vessels. Arteries carry blood away from the heart under high pressure, featuring thick walls with elastic fibers that help maintain pulse flow. Veins return blood to the heart under low pressure and have valves to prevent backflow. Capillaries are tiny vessels where the actual exchange of materials happens between blood and body tissues.
The heart's structure is designed for efficiency. Four valves (tricuspid, bicuspid, pulmonary, and aortic) ensure blood flows in one direction. The septum divides the heart into left and right sides, preventing oxygenated and deoxygenated blood from mixing.
Did you know? Capillaries are so small that red blood cells must pass through them in single file. This tiny size is crucial for allowing efficient exchange of oxygen, nutrients, and waste products between your blood and tissues.
