The phosphate buffer system is maximally effective at a pH close to its p^a of 6.86 (Figs 2-16, 2-18) and thus tends to resist pH changes in the range between about 5.9 and 7.9. It is therefore an effective buffer in biological fluids; in mammals, for example, extracellular fluids and most cytoplasmic compartments have a pH in the range of 6.9 to 7.4.

Blood plasma is buffered in part by the bicarbonate system, consisting of carbonic acid (H2CO3) as proton donor and bicarbonate (HCOjT) as proton acceptor:


This buffer system is more complex than other conjugate acid-base pairs because one of its components, carbonic acid (H2CO3), is formed from dissolved (d) carbon dioxide and water, in a reversible reaction:

Carbon dioxide is a gas under normal conditions, and the concentration of dissolved CO2 is the result of equilibration with CO2 of the gas (g) phase:

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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