The first line of defense against addition of acid or base to the body
Extracellular and intracellular buffers
The second line of defense against addition of acid or base to the body
The respiratory system
What principle states that at equilibrium (when the velocities of the forward and backward reactions are equal), the ratio of the concentration products of opposing reactions is a constant?
Law of mass action
The CO2-HCO3 buffer system is an open or a closed system?
Open buffer system
- In an open buffer system, the buffer pair occurs in 2 separate but communicating compartments (internal and external), separated by a freely permeable barrier (e.g. plasma membrane). The external compartment provides an effective infinite reservoir of the uncharged buffer pair component.
In what pH range is buffer efficiency the greatest?
At a pH range near the pKa'
TRUE/FALSE: Phosphofructokinase is the rate-limiting enzyme of glycolysis. Its activity is enhanced by an acidic environment (low pH) and inhibited by an alkaline environment (high pH).
FALSE. Phosphofructokinase activity is inhibited by a low pH and enhanced by a high pH. Therefore, an increase in pH accelerates glycolysis and generates pyruvate and lactate. It follows that the generation of lactate in patients with lactic acidosis and the generation of ketoacids in patients with ketoacidosis are impeded by acidemia.
TRUE/FALSE: The generation of lactate in patients with lactic acidosis and the generation of ketoacids in patients with ketoacidosis are impeded by acidemia.
TRUE.
Phosphofructokinase activity is inhibited by a low pH and enhanced by a high pH. Therefore, an increase in pH accelerates glycolysis and generates pyruvate and lactate. It follows that the generation of lactate in patients with lactic acidosis and the generation of ketoacids in patients with ketoacidosis are impeded by acidemia.