Arteries – carry blood away from the heart (usually oxygen-rich)

Veins – carry blood to the heart (usually oxygen-poor)

Capillaries – tiny vessels where gas and nutrient exchange happens

Arterioles – smaller branches of arteries

Venules – small veins that collect blood from capillaries

Tricuspid Valve – between right atrium and right ventricle

Pulmonary Valve – between right ventricle and pulmonary artery

Mitral (Bicuspid) Valve – between left atrium and left ventricle

Aortic Valve – between left ventricle and aorta

Right Atrium – receives deoxygenated blood from body

Right Ventricle – pumps blood to lungs

Left Atrium – receives oxygenated blood from lungs

Left Ventricle – pumps oxygenated blood to body

Interatrial Septum – separates left and right atria

Interventricular Septum – separates left and right ventricles

Epicardium – outer layer

Myocardium – muscular middle layer

Endocardium – inner lining