Page 234 - The Miracle of the Blood and Heart

CAPILLARY
Oxygen
transported
into the
blood

Carbon dioxide
Oxygenated transported to
blood the alveolus
ALVEOLUS

Bronchia
Blood cells
Deoxygenated
blood

Cell membrane
Alveolus

Capillary
cell Cytoplasm

Basement
membrane fibers
Oxygenated blood

The barrier between the air in the alveoli
Alveolar
and the blood in the capillaries is a total of cell
4 micrometers thick—equivalent to half
the diameter of a red blood cell. The
extreme fineness of this barrier shows how
Active
very swift and effective the two-way surface layer
exchange of gasses across this barrier is.
Path of oxygen
molecule
Air in lungs
Harun
Yahya

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