During which respiratory process is oxygen distributed to body tissues?

The process during which oxygen is distributed to body tissues is known as internal respiration. This process involves the exchange of gases between the blood and the cells of the body. After oxygen is inhaled into the lungs and transferred to the bloodstream during external respiration, it is then transported via the circulatory system to tissues throughout the body. At the cellular level, oxygen is released from the hemoglobin in red blood cells and diffuses into the surrounding cells where it is used for metabolic processes, particularly in the production of ATP through cellular respiration.

To clarify the other processes mentioned: external respiration refers to the exchange of gases between the lungs and the environment, where oxygen enters the bloodstream and carbon dioxide is expelled. Ventilation relates to the mechanical process of breathing — inhaling and exhaling — that facilitates external respiration. Diffusion is a fundamental physical process that describes how gas molecules move from areas of higher concentration to areas of lower concentration and is part of both external and internal respiration; however, it does not specifically refer to the distribution of oxygen in body tissues. Hence, internal respiration is the most accurate term for the distribution of oxygen to body tissues.