Which blood vessel carries deoxygenated blood to the heart?

Veins are the blood vessels responsible for carrying deoxygenated blood back to the heart. This occurs after the oxygen has been delivered to the body's tissues via the arteries and capillaries. Once the oxygen is utilized by the cells, the blood collects carbon dioxide and other waste products, transforming it into deoxygenated blood. The veins then channel this deoxygenated blood toward the heart, where it is sent to the lungs for re-oxygenation.

In contrast, arteries are primarily responsible for transporting oxygenated blood away from the heart to the various parts of the body. Capillaries serve as the exchange sites where oxygen and carbon dioxide are swapped at the tissue level, and venules, which are small blood vessels that connect capillaries to veins, also carry deoxygenated blood but are not the primary vessels recognized for this function. Thus, veins are correctly identified as the vessels that carry deoxygenated blood back to the heart.