Gaseous Exchange in Humans

Respiring cells need a continuous supply of

(a)  

Gaseous exchange in humans takes place in the

(a)  

Air exhaled has more (a)   than air inhaled.

Blood rich in _____________ flows to the body cells. Blood rich in __________ flows to the lungs.

(a)  

(a)   is the exchange of gases across a respiratory surface.

(a)   is a mechanical process that involves inhaling air.

The lungs are made up of many tiny air spaces called (a)  

The respiratory system in humans and other mammals consists of breathing muscles, air passages and (a)  

During inhalation, air enters the nose and/or mouth, and moves into the (a)  

The bronchi pair branch into smaller and smaller tubes called the (a)