Aspartame is the most controversial food additive in history, and its approval for use in food was the most contested in FDA history. In the end, the artificial sweetener was approved, not on scientific grounds, but rather because of strong political and financial pressure.
The arterioles then divide further into capillaries. Capillaries are the smallest blood vessels and their walls are only one cell thick which allows diffusion between the blood and cells to occur. Nutrients and oxygen from the blood diffuses through the capillary walls into the tissues that need it. This is aided by the relatively high blood pressure that also squeezes the oxygen and nutrients through the capillary wall and into the cells of the tissue.
Capillaries are the smallest blood vessels in the cardiovascular system. Inside each lung, oxygen in the air moves through the wall â¦ s of the alveoli and into the capillaries. In the capillaries, the oxygen binds to red blood cells, which are carried in the blood stream through the rest of the body. As the oxygen rich red blood cells move through the cardiovascular system, they release the oxygen to the body.