What system in the body regulates acid-base balance?

What system in the body regulates acid-base balance?

• A. Buffer
• B. Nervous system
• C. Endocrine system
• D. Circulatory system

Answer: (A)

Chemical buffering systems in body fluids are the body's immediate defense against shifts in acidity and basicity. Buffers, especially the bicarbonate buffer system in blood, act right away to neutralize added acids or bases and keep pH within a narrow range (around 7.35–7.45 in blood). Mechanistically, when acid enters, buffering pairs like bicarbonate (HCO3−) bind hydrogen ions to form carbonic acid (H2CO3), which is then converted to CO2 and water that we exhale. When base is added, carbonic acid dissociates to release H+ and form bicarbonate, tempering the rise in pH. This rapid action is why the buffer system is the primary regulator of acid-base balance. The respiratory system and kidneys provide longer-term adjustments by altering CO2 levels and bicarbonate/H+ excretion, respectively, but the buffering system is the immediate regulator that maintains pH stability.

Chemical buffering systems in body fluids are the body's immediate defense against shifts in acidity and basicity. Buffers, especially the bicarbonate buffer system in blood, act right away to neutralize added acids or bases and keep pH within a narrow range (around 7.35–7.45 in blood). Mechanistically, when acid enters, buffering pairs like bicarbonate (HCO3−) bind hydrogen ions to form carbonic acid (H2CO3), which is then converted to CO2 and water that we exhale. When base is added, carbonic acid dissociates to release H+ and form bicarbonate, tempering the rise in pH. This rapid action is why the buffer system is the primary regulator of acid-base balance. The respiratory system and kidneys provide longer-term adjustments by altering CO2 levels and bicarbonate/H+ excretion, respectively, but the buffering system is the immediate regulator that maintains pH stability.