Internal medicine is the type of medical care that deals with adult health and pulmonology are one of its many fields. Pulmonologists focus on the respiratory system and diseases that affect it.
Mouth and nose.
Sinuses
Throat (pharynx)
Voicebox (larynx)
Windpipe (trachea)
Bronchial tubes
Lungs and things inside them like bronchioles and alveoli.
Diaphragm