I WONDER - What Job Do Veins Do?

The video explains that veins hold about 70% of the body's blood, which travels to the heart and lungs to receive oxygen. The blood in veins is deoxygenated. The largest vein is the inferior vena cava, returning blood from the lower body to the heart, while the longest is the saphenous vein in the leg. Venules are small veins that connect larger veins to capillaries.

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