Breathing And Exchange Of Gases — 6-topic bundle

Breathing, or ventilation, is a two-step process: inspiration (inhaling) and expiration (exhaling). Both steps rely on changing the volume of your thoracic cavity (your chest) and, consequently, the pressure inside your lungs.

When you inhale, it's an active process, meaning it requires muscle contraction. Here's what happens:

Respiration isn't just breathing; it's a two-part process. External respiration (which we often just call "breathing") is the physical act of getting air into and out of your lungs. Internal respiration is the exchange of gases (oxygen and carbon dioxide) between your blood and your body cells. Both are crucial for life.