Through which system are oxygen and carbon dioxide transported between body cells and the respiratory system?

• A. Nervous system
• B. Endocrine system
• C. Circulatory system
• D. Muscular system

Answer: (C)

The transportation of oxygen and carbon dioxide between body cells and the respiratory system is primarily facilitated by the circulatory system. This system consists of the heart, blood vessels, and blood, which all work together to distribute essential substances throughout the body.

When you breathe in, oxygen enters the lungs, where it diffuses across the alveolar membrane into the blood. Red blood cells then bind to this oxygen and carry it away to the tissues and organs. At the cellular level, oxygen is utilized for metabolic processes, producing carbon dioxide as a waste product. This carbon dioxide is then transported back to the lungs via the blood, where it is expelled from the body when you exhale.

This efficient exchange of gases—oxygen uptake and carbon dioxide removal—is critical for cellular respiration and overall metabolic function, making the circulatory system vital for maintaining homeostasis and proper physiological function. Other systems like the nervous, endocrine, and muscular systems play important roles in bodily functions but do not specialize in the transport of gases in this context.