Acid-Base Balance and Reproductive Systems

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1. How are carbonic and lactic acid produced?
Carbonic acid is produced when CO2 that has been produced by cellular respiration is combined with H2O. This produces H2CO3 (carbonic acid). Then, in the plasma (for example), H2CO3 ionizes to form H+ and HCO3- (bicarbonate ion). On the other hand, lactic acid is formed when pyruvate (from glycolysis) is reduced into lactate during anaerobic fermentation because there isn't enough O2 in the cells to oxidize pyruvate in the Krebs cycle.

2. Are fruits and vegetables acid-forming or base-forming foods?
When sugars are metabolized, lots of carbon-containing acids are produced (like lactate, citrate, etc.). Therefore, on the surface, it would appear that all foods are acid-forming; however, these acids are oxidized even further (to CO2) and don't stay in the blood too long (being released into the atmosphere by CO2). Foods also contain minerals. These minerals can also affect the pH of the body, and it is usually these minerals which are under discussion when we speak of acid-forming or base-forming foods. Most fruits and vegetables leave an alkaline residue in the body (after the sugars are oxidized) because of their mineral content. There are exceptions to this general rule, but it is usually true.

3. Identify several acid-forming elements.
Acid-forming foods are typically foods rich in protein, such as red meat. Other examples are coffee, alcohol, and blueberries.

4. What is a physiological buffer?
A physiological buffer is a biological buffer that works in the body to dampen changes in pH caused by metabolism. Some examples are the bicarbonate/carbonate buffer, the blood protein hemoglobin, the dihydrogen phosphate/monohydrogen phosphate buffer system, and the titratable ...