← Chapter 26
Anatomy & Physiology · Chapter 26
Blood pH & Buffers
Blood pH must stay in a razor-thin band —
7.35 to 7.45
. Add acid or base and watch the
bicarbonate buffer
fight to hold the line.
Blood pH: 7.40
Blood pH
7.35 – 7.45
+ Add acid (H⁺)
+ Add base
↺ Reset
Bicarbonate buffer:
CO₂ + H₂O ⇌ H₂CO₃ ⇌ H⁺ + HCO₃⁻. Add acid → HCO₃⁻ mops up the H⁺. Add base → carbonic acid releases H⁺. The equation shifts to blunt the change.
📷 Reference image
A real labeled figure to compare with the interactive above.
Blood pH & Buffers — OpenStax, CC BY 3.0 (via Wikimedia Commons)