Diffusion. O2 moves from an area of higher concentration to a lower concentration.
capillaries
Oxygen and other gases pass through the capillaries.
Capillaries
The alveoli and capillaries in the lungs pass oxygen to the blood. Both have very thin walls, which allow the oxygen to pass from the alveoli to the blood. The capillaries then connect to larger blood vessels, called veins, which bring the oxygenated blood from the lungs to the heart.
It is the heart that pumps fresh oxygen in the blood.
In the capillaries surrounding the alveoli in the lungs
Capillaries
Capillaries
Capillaries
Capillaries are very thin blood vessels. Oxygen and nutrients and hormones can pass through the walls of the capillaries and reach the body's cells, while red blood cells remain in the capillaries.
Oxygen is transported by red blood cells and is released into tissues as they pass through capillaries in the tissue.
No, all gas exchange is done through capillaries. Both veins and arteries are too thick and contain muscle layers that prevent gas exchange. However, capillaries are small enough (blood cells can only pass through one at a time) that oxygen can pass to the tissues and carbon dioxide can pass to the RBCs.