The Respiratory System Utilizing knowledge from your learning and assigned readings, respond to the following questions: What are the primary functions of the respiratory system? Explain the roles of mucus and cilia in the respiratory system. Explain the structure and function of the respiratory membrane. Identify and describe the four distinct events that are collectively called respiration. After a long scuba diving session on a Caribbean reef, a patient boards a plane to Dallas. He begins to feel pain in his elbow on the flight back to Dallas. What is happening to him? Explain how hyperventilation and hypoventilation alter levels of carbon dioxide in the blood.