What is the normal arterial blood pH range?

• A. 7.25-7.35
• B. 7.35-7.45
• C. 7.45-7.55
• D. 6.8-7.2

Answer: (B)

The normal arterial blood pH range is typically from 7.35 to 7.45. This range is critical for maintaining optimal physiological function because even slight deviations can lead to significant metabolic disturbances. A pH below 7.35 indicates acidosis, which can disrupt cellular processes and enzyme activities, while a pH above 7.45 indicates alkalosis, which can also impair physiological functions and potentially lead to neuromuscular excitability issues.

The body tightly regulates blood pH through mechanisms involving the respiratory system (by varying carbon dioxide levels) and the kidneys (by adjusting bicarbonate and hydrogen ion concentrations). Understanding this normal range is fundamental for recognizing and interpreting various clinical conditions related to acid-base imbalances.