Biological buffers Flashcards
What is the pH of blood?
7.35 - 7.45
Describe the changes in pH
Acidosis is when the pH is below 7.35.
Alkalosis is when the pH is above 7.35
State and explain endogenous buffers.
Blood : haemoglobin and bicarbonate
Intracellular buffers : proteins and phosphate
* Bicarbonate buffer system is dependent is dependent on atmosphere
*Kidneys regulate bicarbonate levels
Where does H+ com from?
Cellular respiration/Metabolism : CO2 –> carbonic acid
Anaerobic respiration : lactic acid
Keto acidosis
What is the first line of defense against a pH shift?
Chemical buffer system
What is the second line of defense against a pH shift?
Physiological Buffers.
State all chemical buffer systems.
Bicarbonate buffer system
Phosphate buffer system
Protein buffer system
**These act in seconds
State all physiological buffers.
Respiratory mechanism (CO2 excretion)
**This acts in 1-3 mins
Renal mechanism (H+ excretion)
**These takes hours to days
What are the types of acid-base disorders?
Metabolic acidosis/alkalosis
Respiratory acidosis/alkalosis
Explain Metabolic acidosis/alkalosis
When the concentration of HCO3- decreases, that leads to metabolic acidosis.
When the concentration of HCO3- increases, that leads to metabolic alkalosis.
Explain Respiratory acidosis/alkalosis
When the concentration/levels of PaCo2 increase, this leads to respiratory acidosis.
When the concentration/levels of PaCo2 decrease, this leads to respiratory alkalosis.
What happens in respiratory acidosis?
What happens in respiratory alkalosis?
What happens in metabolic acidosis?
What happens in metabolic alkalosis?
