Why is external and internal respiration essential?

External respiration is essential because it facilitates the exchange of oxygen and carbon dioxide between the lungs and the atmosphere, ensuring that oxygen is supplied to the bloodstream for cellular functions. Internal respiration, on the other hand, occurs at the cellular level, allowing oxygen to be utilized by cells for metabolism while removing carbon dioxide as a waste product. Together, these processes are crucial for maintaining the body’s homeostasis, supporting energy production, and sustaining life. Without efficient respiration, cells would be deprived of oxygen, leading to tissue damage and organ failure.