The formation of definitive alveoli by secondary septation of primitive saccules is effectively an essentially postnatal event: if the alveolar phase of human lung development extends from about ...
When air goes down into the lungs, it passes through smaller and smaller tubes and ends up in tiny air sacs called alveoli. Oxygen passes through the walls of the alveoli and enters tiny blood ...
Gas exchange is a process that involves the swapping of gases that occurs at exchange surfaces such as the alveoli found within your lungs. Gas exchange allows oxygen to travel into your cells for ...