Blood pH and Life

If there is abundant literature showing that the presence of K is dependent on the availability of oxygen, there are also several experiments showing its relation to hydrogen, for according to our reaction, K + H = Ca. In other words, if K is too abundant in the presence of H, it will give Ca.

The presence of H is linked to acidity ( low pH ). An excess of H ions signifies an acidity that might become dangerous for the cell. However, in that case K can join an H nucleus to produce Ca, thereby establishing alkalinity and an optimum Ca/K ratio. The agent of equilibrium is thus K. The effects between K and Ca are opposite in appearance only; they are in fact complementary.

Hoagland writes that there is a clear tendency toward acidification of the of the cellular medium, freezing H⁺ ions; the addition of K⁺ ions leads to the alkalinization of the cellular liquids.

Reinberg notices that "the alkalinization of the cellular liquids with K is well known by arboriculturists, who use potassium nitrate to speed up fruit maturation."

It is of interest to point out that the proportions of K and Ca are of the same order in animal life — in the plasma as well as in seawater, where life began.

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Darrow pointed out that a K increase in the cell decreases the cell's acidity because it causes a decrease in H. Thus the alkalinization takes place when K takes H to give Ca. Ca is taken back by the outside liquid and excreted, producing a negative Ca balance sheet. More Ca is excreted than ingested, but the main source of Ca is Mg.

The internal equilibrium of the animal cell postulates a large K content and a small Ca content. The reactions with H help to reduce acidification, since H is taken away.

It has been found that micro-organisms in the soil excrete H ions which acidify the soil; however, K neutralizes this acidity when it comes in contact with the roots.

If the calcium concentration in the nutritive medium is increased, there is a smaller absorption of K. This can be explained by the fact of reversibility.

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This specific reaction allows a biological equilibrium to be maintained.