The normal pH range of blood is 7.35 to 7.45, which is crucial for maintaining physiological processes. This range is tightly regulated by the body, as even slight deviations can lead to significant metabolic disturbances. A blood pH lower than 7.35 indicates acidosis, while a pH higher than 7.45 indicates alkalosis, both of which can disrupt cellular functions and lead to serious health issues.
The body employs several mechanisms to maintain this pH range, including buffer systems, respiration, and renal function. The bicarbonate buffer system, for example, plays a key role by neutralizing excess acids or bases in the blood, thus maintaining the stability of the pH level.
In contrast, the other ranges presented are either too acidic or too alkaline for normal human physiology. Blood pH cannot naturally fall below 7.35 or rise above 7.45 without causing health problems, making the selected range the only appropriate one for normal blood pH.