The body cells of the human organism are namely surrounded by the so called extra cellular fluid, offering the cells a similar milieu as probably the single-celled organisms might had found.
This extra cellular fluid belongs to the connective tissue. That has not only a backing function filling the intercellular space, but also a regulating function, which is so important that the connective tissue is also called "basic regulation system". Hereby the water seems to have a central task. All arterial capillaries - as well as the nerves - are ending in this connective tissue; and in the venous capillaries are staring here, as well as the lymphatic course. Thereby neither the bloodstreams nor the nerves have a direct contact to the cells. Furthermore all transports of nutrients as well of waste products happen in the connective tissue, just as the transport of oxygen and carbon dioxide. Also: All substances like glucose, hormonal information, transmitters from the nerve endings as well as electric impulses reach the cell only through this offshore extra cellular milieu, the water of the connective issue. The Bio Disc