S.1.2 Structure of the Respiratory System

breathing/inhaling & exhaling

the process of bringing oxygen into the lungs

ventilation

the process of exchanging oxygen with carbon dioxide in the lungs

pharynx

throat

trachea

large tube reinforced by cartilage rings that keep it from collapsing

alveoli

* single-celled, thin-walled structures that look like clusters of grapes
* sites of gas exchange
* have type II alveolar cells that release a lipoprotein (surfactant) that reduces the surface tension

structures that form respiratory system

* air enters nasal openings & moves into nasal cavity
* air travels past the pharynx & into the trachea
* air continues to the first division of trachea
* right & left bronchi
* air in right bronchus → right lung
* air in left bronchus → left lung
* right & left lung bronchi subdivide into smaller tubes (bronchioles)