Question

What is it about the structure of the alveolar-capillary unit that makes diffusion possible? Select all that apply.

The capillaries are large.

The cell wall of the alveoli is thin.

Many capillaries surround one alveoli sac.

There is always low pressure in the alveolar-capillary unit.

The alveolar-capillary unit provides a large surface area.

Answer 1

The cell wall of the alveoli is thin.

The alveolar-capillary unit provides a large surface area.