Geoff G. answered • 03/25/21
Current A&P Instructor with Extensive Physiology Experience
This is a really odd question, and I recommend asking whoever asked you the question for clarification. Some of the divisions of "structures" can be quite arbitrary. Is "nose" one structure or do the vestibule and nasal cavity count as two structures? Is the pharynx one structure or three (naso, oro, and laryngopharynx)? There are divisions within the larynx, not to mention that there are over 20 orders of branching from the trachea to the terminal bronchioles. What kind of alveoli are we talking about? It could be a single alveolus accessed from a respiratory bronchiole, but if it's an alveolus within an alveolar sac it would also have to travel through an alveolar duct.
The question is a trick question at best and an uninformed or completely ambiguous question at worst.
The second part of the question is more objective. The respiratory zone is where gas exchange can take place which is to say anywhere where alveoli are found. This includes respiratory bronchioles and alveolar ducts and sacs. The conduction zone is everything starting with the nose and before the respiratory bronchioles. As the name implies, these structures conduct inspired air to the areas where gas exchange (respiration) can take place.
