Which blood vessel type is primarily responsible for returning deoxygenated blood back to the heart?

The primary function of veins is to return deoxygenated blood back to the heart. Veins are equipped with one-way valves to help prevent backflow and facilitate the movement of blood against the force of gravity, especially in the limbs. They have thinner walls than arteries, allowing them to be more flexible and able to accommodate varying volumes of blood.

While arteries are responsible for carrying oxygenated blood away from the heart, capillaries play a crucial role in the exchange of gases, nutrients, and waste products between blood and tissues, but they do not transport blood back to the heart. Pulmonary vessels specifically refer to those involved in the pulmonary circulation system, which includes pulmonary arteries and veins that transport blood between the heart and lungs. However, in terms of the broader circulatory system, veins are the blood vessels primarily tasked with carrying deoxygenated blood back to the heart.