a: Gross anatomy of lung and thorax. b: Microscopic anatomy of bronchial wall. C: View of terminal airway and alveoli. d: Alveolar structure.

In contrast, diffusion of gases between inhaled air entering the lungs and capillaries occurs within the lungs. Circulation in the fish is accomplished by a two-chambered heart, whereas a four ...

The skeleton provides the framework for muscles and gives the body its defined human shape ... and the blood that flows through them. Respiratory system - Edexcel The respiratory system transports ...