The intercellular substance (plasma) is a constituent of the blood.
A small amount of blood plasma flows all the time through the walls of the capillaries (small vessels), thus a liquid appears, which is located around all living cells of the body. From this fluid, cells absorb useful and necessary substances and trace elements, as well as oxygen, while releasing carbon dioxide and other compounds of trace elements from it. The blood nourishes the tissue fluid with the substances used by the cells and takes back the unnecessary ones.
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