Answer:
The human body requires a pretty unique balance, a very strict balance at that, between acidity and alkalinity. This means that the body has a series of mechanisms that will ensure that our entire system is constantly kept between the ranges of 7.35 and 7.45 of acidity and alkalinity. If ever the scale should tip either below 7.35, or above, 7.45, then we would be talking about an imbalance in the acid-base system and we would be facing serious problems. Given this explanation, the answers would be thus:
1. The normal acid-base balance is when the ratio of carbonic acid (represented in presence of CO2 molecules in blood) to bicarbonate ions, is 20:1. This means that the body´s pH is precisely between the range of 7.35 and 7.45. However, when the ratio above changes, and the number of molecules of CO2 rise, tiping the scale, and the pH goes below 7.35, we are talking about a respiratory acidosis. When we are talking that either bicarbonate is not being produced in enough quantities, or not produced at all to lower the pH of the blood, and other acidic metabolites are being added to the bloodstream further lowering pH, then we are talking about a metabolic acidosis. On the other end, if the levels of CO2 are too low because they are being released by a rapid breathing, and oxygen levels are too high, the blood becomes too alkaline and we will be talking about respiratory alkalosis. Also, when bicarbonate ions are produced in massive quantities, upsetting the scale of 20:1 with respect to CO2 levels, and furthermore, the urine starts excreting both H+ ions and bicarbonate, we are talking about metabolic alkalosis.
2. As said, the ratio of bicarbonate to carbonic acid must remain within 20:1, otherwise a person´s alkaline-acid balace will be upset. If either the bicarbonate to carbonic acid, or the pH, in the body are altered in any way, the body will activate both respiratory and metabolic mechanisms to restore the balance. If this is not achieved, then outside help will be required and the person will show the symptoms that will allow professionals to know what is going on, and how to turn it back to its normal balance.
