Acids and buffer systems Flashcards
When is the body in acid base balance?
when H+ production= H+ loss and pH of body fluids are within normal limits
Sulfuric and Phosphoric acid are examples of what?
Fixed acids
Why are metabolic, volatile and fixed acid important?
they threaten the pH balance
What is acidosis caused by?
caused by the plasma pH being less than 7.35
Why is severe acidosis deadly?
CNS deteriorates, causing a coma
cardiac contractions become weaker
What is the most important factor affecting pH of body tissues?
partial pressure of carbon dioxide
Carbon dioxide + Water =?
carbonic acid
What does the buffer system consist of?
weak acid
anion released by its dissaciation
What are the three major buffer systems?
Phosphate buffer system
Protein buffer system
Carbonic acid bicarbonate buffer system
What is the only intracellular buffer system that can have an immediate effect on the pH of body fluids?
hemoglobin buffer system
What happens in the hemoglobin buffer system?
In tissues RBCs absorb CO2 from plasma and convert it to carbonic acid
What do protein buffer systems contribute to and how do they do it?
regulation of pH in ECF and ICF
by binding to excess hydrogen ions
What do carbonic acid bicarbonate buffer systems involve and what do they protect against?
involve freely reversible reactions
protects agaisnt the effects of acids
What is the bicarbonate reserve?
body fluid in the form of sodium bicarbonate
What are metabolic acid-base disorders caused by?
production or loss of excessive amounts of fixed or organic acids
Respiratory acid-base disorders are caused by…?
result from an imbalance of CO2 generation and elimination
How is metabolic acidosis developed?
when large numbers or H+ are released by organic or fixed acids and pH decreases
What are the responses to restore homeostasis in metabolic acidosis?
respiratory response
renal response
What happens in the respiratory response?
increase respiratory rate
converting more carbonic acid to water
What happens in the renal response?
secrete more H+ ions into urine
removing co2
How does metabolic alkalosis develop?
many H+ removed
pH is then raised
What are the kidneys responses to metabolic alkalosis?
rate of H+ declines
What are the responses by the kidney to restore homeostasis?
decreased respiratory rate
convert more co2 into carbonic acid
What do respiratory acid-base disorders result from?
imbalance between the rate of co2 generation in body tissues and the rate of co2 elimination at the lungs
