Physiological pH and Its Regulation
Start with the big picture
Arterial pH normally ranges from 7.35 to 7.45, and because pH is logarithmically related to hydrogen ion concentration, small pH shifts can reflect substantial changes in [H⁺]. Bicarbonate, phosphate, and proteins provide buffering; the bicarbonate–carbonic acid system is especially important because its components can be regulated. The lungs adjust carbon dioxide through ventilation, while the kidneys retain or regenerate bicarbonate and excrete fixed acids. These mechanisms differ in timing and work together to maintain balance. The topic also introduces acidosis and alkalosis, the anion gap as a tool for classifying metabolic acidosis, and the use of compensation predictions to help identify possible mixed disorders.
What you'll learn
- Relate arterial pH to hydrogen ion concentration.
- Describe the major body buffer systems and the bicarbonate buffer relationship.
- Explain how respiratory and renal mechanisms regulate acid–base balance.
- Define acidosis, alkalosis, and the anion gap in the context of classification.
- Recognize how compensation predictions can help identify mixed disorders.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
