Chapter 7: Problem 92
The most important buffer in blood consists of (1) \(\mathrm{HCl}\) and \(\mathrm{Cl}\) (2) \(\mathrm{H}_{2} \mathrm{CO}_{3}\) and \(\mathrm{HCO}_{3}\) (3) \(\mathrm{H}_{2} \mathrm{CO}_{3}\) and \(\mathrm{Cl}\) (4) \(\mathrm{HCl}\) and \(\mathrm{HCO}_{3}\)
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
bicarbonate buffer system
The way this works is through a dynamic equilibrium. When the pH of the blood rises, indicating a more basic environment, carbonic acid releases hydrogen ions (H\(^+\)), which helps to lower the pH. Conversely, when the pH falls, indicating a more acidic environment, bicarbonate binds with hydrogen ions, helping to raise the pH.
Through these reactions, the bicarbonate buffer system ensures our blood remains at an optimal pH, typically around 7.4.
buffers
In the context of blood, the bicarbonate buffer system is the primary buffer. It includes carbonic acid, a weak acid, and bicarbonate, its conjugate base. By toggling between these two forms, the buffer can neutralize added acids or bases, thus stabilizing the pH.
Without buffers, even minor fluctuations in hydrogen ion concentrations could lead to significant shifts in pH, potentially disrupting biochemical processes and endangering cellular function.
acid-base balance
The bicarbonate buffer system is a key player in maintaining this balance. When the blood becomes too acidic (low pH), the bicarbonate can neutralize the excess H\(^+\) ions. Conversely, when the blood becomes too alkaline (high pH), carbonic acid can release H\(^+\) ions to correct the imbalance.
Maintaining this balance is critical for enzymes, proteins, and other molecules, which need a specific pH to perform their functions. Disruptions in the acid-base balance can lead to conditions such as acidosis or alkalosis, both of which pose significant health risks.
carbonic acid and bicarbonate
In the bicarbonate buffer system, these components interact to stabilize pH. When the pH increases, signaling a more basic environment, carbonic acid dissociates into bicarbonate and H\(^+\) ions, counteracting the rise in pH. When the pH decreases, indicating a more acidic environment, bicarbonate combines with H\(^+\) ions to form carbonic acid, helping to raise the pH.
Therefore, the dynamic interplay between carbonic acid and bicarbonate helps maintain a stable and healthy pH level in the blood, contributing to overall homeostasis.