What is the primary function of the respiratory system?

The primary function of the respiratory system is to facilitate the exchange of oxygen and carbon dioxide between the body and the environment. This process occurs in the lungs, where oxygen from inhaled air passes into the bloodstream while carbon dioxide, a waste product of metabolism, is expelled from the blood into the exhaled air. The efficiency of this gas exchange is crucial for maintaining homeostasis and supporting cellular respiration, which is vital for energy production in the body.

In contrast, the role of transporting nutrients to cells involves the circulatory system, as it is responsible for delivering essential substances throughout the body. Filtering toxins from the blood is primarily the responsibility of the kidneys within the urinary system, which cleanses the blood and helps maintain electrolyte balance. Regulating hormonal balance is a function of the endocrine system, which secretes hormones to control various physiological processes. Each of these systems has distinct roles, but the respiratory system is specifically aimed at gas exchange, which is essential for life.