PhysiologyTest3 Flashcards
define acidemia and alkalemia
Acidemia is the condition in which the plasma pH falls below 7.35…physiological state that results is acidosis.
Alkalemia exists when the plasma pH is above pH 7.45…physiological state that results is alkalosis
what is the most important factor affecting the pH of the ECF
The dissociation of carbonic acid is the most important factor.
The partial pressure of carbon dioxide because when combined with water, it forms carbonic acid
Summarize the relationship between CO2 levels and pH
an inverse relatinship exists between pH and CO2 levels. when carbon dioxide levels rise, pH goes down. when PCO2 falls, there is increase in pH
Identify the body’s 3 major buffer systems
the bodies 3 major buffers systems are the
protein
carbonic acid-bicarbonate
phosphate buffer
Describe the carbonic acid-bicarbonate buffer system
The carbonic acid-bicarbonate buffer system prevents pH changes caused by organic acids and fixed acids generated by metabolic activity. It uses the H+ released by these acids to generate carbonic acid, which dissociates into H2O and CO2, the latter of which is exhaled from the lungs
Describe the roles of the phosphate buffer system
The phosphate buffer system plays and important role in buffering the pH of the ICF and the urine
Fixed acids
acids that do not leave solution; once produced, they remain in body fluids until they are eliminated at the kidneys. sulfuric acid and phosphoric acid are the most important fixed acids in the body. these are generated in small amounts during the catabolism of amino acids and compounds that contain phosphate groups, including phospholipids and nucleic acids
Organic acids
acids participates in, or byproducts of, cellular metabolism. lactic acid (produced by the anaerobic metabolism of pyruvate) and ketone bodies are important (synthesized by Acetyl-CoA) under normal conditions, most organic acids are metabolized rapidly. Significant accumulation do not occur
Volatile Acids
these can leave the body by entering the atmosphere at the lungs(external expiration). carbonic acid is volatile acid that forms through the interactions of water and carbon dioxide``
describe metabolic acidosis
it results from the depletion of the bicarbonate reserve, caused by an inability to excrete hydrogen ions at the kidneys, the production of large numbers of fixed and organic acids, or bicarbonate loss
describe metabolic alkalosis
metabolic alkalosis results when bicarbonate ion concentrations become elevated
if the kidneys are conserving HCO3 and eliminating H+ in acidic urine, which is occurring? metabolic alkalosis or metabolic acidosis
the kidneys conserve HCO3 and eliminate H in the urine during metabolic acidosis
define respiratory acidosis and respiratory alkalosis
respiratory acidosis is lowered blood pH resulting from inadequate respiratory activity and is characterized by elevating levels of carbon dioxide; respiratory alkalosis is elevated blood pH due to excessive respiratory activity which depresses carbon dioxide levels and elevates the pH of body fluids
what would happen to the plasma PCO2 of a patient who has an airway obstruction
the plasma PCO2 of a patient with an airway obstruction would increase, resulting in respiratory acidosis
how would a decrease in the pH of body fluids affect the respiratory rate
A decrease in the pH of body fluids would cause an increase in the respiratory rate
