Question

what is the primary function of the respiratory system? *
producing blood cells
protecting organs
exchanging oxygen and carbon dioxide
regulating hormones

Explanation:

• "Producing blood cells" is a function of the skeletal system (bone marrow), not the respiratory system.
• "Protecting organs" is a function of the skeletal and integumentary systems, not the respiratory system.
• The respiratory system (including lungs, airways, etc.) is responsible for gas exchange—taking in oxygen and releasing carbon dioxide.
• "Regulating hormones" is a function of the endocrine system, not the respiratory system.

Answer:

C. Exchanging oxygen and carbon dioxide