What is the term for the complex system that involves arteries carrying oxygenated blood to tissues and veins bringing deoxygenated blood back to the heart?

The term "circulation" specifically refers to the complex system of blood flow through the body, where arteries transport oxygenated blood away from the heart to deliver oxygen and nutrients to tissues. Subsequently, veins return deoxygenated blood back to the heart for re-oxygenation in the lungs. This process is vital for maintaining the body's overall function, ensuring tissues receive the necessary oxygen for metabolism and removing carbon dioxide and other waste products.

In contrast, respiration relates to the process of gas exchange, predominantly involving the lungs and the intake of oxygen and expulsion of carbon dioxide, but does not encompass the entire blood flow mechanism. Ventilation is a specific aspect of respiration focusing on the movement of air in and out of the lungs, while filtration typically refers to the separation of substances, which does not apply to the circulatory system. Hence, circulation accurately captures the essence of the described process of blood flow in the body.