Anatomy and Organization of the Respiratory System

Practice: A 16-year-old female presents to the emergency department with a 2-hour history of difficulty breathing. She is diagnosed with an asthma attack, which is caused by excessive constriction of smooth muscle in the walls of her airways. Which of the following is the part of her airways that has the most smooth muscle and is thus contributing most to her asthma attack?

Practice: A 57-year-old male presents to his primary care physician complaining of a chronic cough. He reports that he feels the need to cough because his lungs are full of mucus; indeed, his coughs bring up large amounts of greenish-brown mucus. He has smoked two packs of cigarettes per day for the last forty years. Which of the following parts of his respiratory tract has been damaged by his smoking, causing mucus to accumulate in his lungs?