Florida Nursing Assistant Competency Pracrice Exam

What is the primary purpose of the respiratory system?

1. To supply nutrients and eliminate waste

2. To supply oxygen and eliminate carbon dioxide

3. To regulate body temperature

4. To circulate blood throughout the body

The correct answer is: To supply oxygen and eliminate carbon dioxide

The primary purpose of the respiratory system is to supply oxygen to the body and eliminate carbon dioxide. This system plays a critical role in the process of gas exchange, which occurs in the lungs. When we inhale, oxygen from the air enters the alveoli in the lungs, where it diffuses into the bloodstream and is transported to cells throughout the body. Simultaneously, carbon dioxide, a waste product of cellular metabolism, is transferred from the blood into the alveoli and expelled from the body during exhalation. This constant exchange of gases is vital for maintaining cellular respiration and ensuring that the body functions correctly. Other options, while important processes in the body, do not accurately reflect the primary function of the respiratory system. For example, supplying nutrients and eliminating waste pertains more to the digestive and excretory systems, while regulating body temperature involves the integumentary system. Circulating blood is the main function of the cardiovascular system, which works parallel to the respiratory system but is distinct from it.