lymph
blood has a higher protein concentration than the tissue fluids
Oxygen passes into the capillaries that surround the alveoli. The thin walls of the capillaries make this diffusion easier.
Oxygen
oxygen
Carbon dioxide is exhaled
Blood passes through the capillaries, which provide a passage way for the blood from the arteries to the veins. The tiny, thin walled capillaries also allow for the exchange of gases through the tissue. You can read more about capillaries at fi.edu
oxygen
The tiniest tubes that carry blood are the capillaries. These connect arteries and veins.
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.
Oxygen passes from the blood into organs through the wall of capillaries.
aerteries
Carbon dioxide passes into the blood at the capillaries of the systemic circulation. Then it is released at capillaries around the alveoli.
Carbon dioxide is produced as a waste product of respiration, and is taken in the bloodstream to the capillaries outside the lungs, where the CO2 diffuses into the alveoli of the lungs.