Protective systems regulating hydrogen ion concentration in body fluids are known as what?

Protective systems regulating hydrogen ion concentration in body fluids are known as what?

• A. Buffer systems
• B. Enzyme systems
• C. Hormonal systems
• D. Antacid systems

Answer: (A)

Buffer systems are protective systems that regulate hydrogen ion concentration in body fluids. Buffers resist changes in pH by neutralizing added acids or bases, acting almost instantly to prevent sharp shifts. In blood, the carbonic acid–bicarbonate buffer is the primary system, with phosphate and protein buffers contributing as well. While buffers provide immediate defense, the lungs and kidneys handle longer-term adjustments—exhaling CO2 to modulate acidity and reabsorbing or excreting bicarbonate and hydrogen ions to fine-tune pH over time. The other options describe broader roles (enzymes as catalysts, hormones as regulators of many processes, antacids as external agents) and do not function as the body's immediate chemical buffering systems for hydrogen ion concentration.

Buffer systems are protective systems that regulate hydrogen ion concentration in body fluids. Buffers resist changes in pH by neutralizing added acids or bases, acting almost instantly to prevent sharp shifts. In blood, the carbonic acid–bicarbonate buffer is the primary system, with phosphate and protein buffers contributing as well. While buffers provide immediate defense, the lungs and kidneys handle longer-term adjustments—exhaling CO2 to modulate acidity and reabsorbing or excreting bicarbonate and hydrogen ions to fine-tune pH over time. The other options describe broader roles (enzymes as catalysts, hormones as regulators of many processes, antacids as external agents) and do not function as the body's immediate chemical buffering systems for hydrogen ion concentration.