Worksheetsasam basa
Total questions: 97
Worksheet time: 49mins
Which set lists major physiological buffer systems that directly neutralize acids in body fluids?
Bicarbonate phosphate hemoglobin
Lactate citrate albumin only
Ammonia urea creatinine only
Cholesterol triglyceride lipoprotein
Homeostasis of body pH is primarily maintained by which coordinated organs and mechanisms?
Buffers lungs and kidneys
Skin liver and pancreas
Heart spleen and lymph
Muscles bones and joints
Approximately how does the body defend against daily acid produced by metabolism, as depicted?
Buffering and CO2 exhalation plus NH4+ excretion
Storing acids in adipose tissue for weeks
Converting all acids to glucose for reuse
Eliminating acids only through sweating
In erythrocytes, what role does hemoglobin play in acid–base balance?
Buffers hydrogen ions derived from carbonic acid
Generates bicarbonate by de novo synthesis
Pumps CO2 directly into alveolar spaces
Oxidizes CO2 to carbon monoxide gas
Which change most immediately increases blood pH during acute metabolic acidosis?
Increased alveolar ventilation removing CO2
Decreased bicarbonate reabsorption in kidneys
Enhanced anaerobic glycolysis in muscles
Reduced hemoglobin buffering capacity
Which statement best describes renal handling of bicarbonate in acid–base balance?
Filtered bicarbonate is reabsorbed and new bicarbonate is generated
All filtered bicarbonate is excreted unchanged in urine
Bicarbonate is converted to CO2 only in the liver
Kidneys secrete bicarbonate directly into plasma
Which urinary component reflects renal excretion of acid equivalents during acidosis?
Ammonium ion NH4+ in urine increases
Bicarbonate concentration in urine increases
Ketone bodies in urine always disappear
Sodium reabsorption in urine increases
What immediate chemical reaction links CO2 transport to bicarbonate formation in plasma and erythrocytes?
CO2 combines with H2O forming H2CO3
CO2 binds directly to HCO3− forming H2CO4
CO2 precipitates with Ca2+ forming CaCO3
CO2 reacts with O2 forming carbon peroxide
Which scenario would most likely decrease blood pH if uncompensated?
Hypoventilation retaining CO2
Increased renal NH3 production
Enhanced hemoglobin buffering
Bicarbonate reabsorption upregulated
Which buffer pair primarily operates in the extracellular fluid to resist pH change?
Carbonic acid bicarbonate pair
Dihydrogen phosphate urate pair
Hemoglobin methemoglobin pair
Ammonia ammonium pair
During tissue CO2 loading, what typically happens inside erythrocytes to maintain electroneutrality?
Chloride shifts into cells as HCO3− exits
Potassium shifts out as NH4+ enters
Sodium shifts in as H2CO3 exits
Calcium shifts out as CO2 enters
Which kidney process most directly removes free hydrogen ions from the body?
Secretion of H+ in distal nephron and trapping as NH4+
Filtration of H+ at the glomerulus without reabsorption
Reabsorption of H+ along with bicarbonate in proximal tubule
Conversion of H+ to glucose via renal gluconeogenesis
Which chemical equilibrium best represents carbonic acid formation in blood plasma?
CO2 + H2O ⇌ H2CO3
CO2 + O2 ⇌ H2CO3
H2CO3 ⇌ CO2 + O2
H2CO3 + O2 ⇌ CO2 + H2O
In the Henderson–Hasselbalch form for the bicarbonate buffer, which variable reflects dissolved CO2 via Henry’s law?
S × pCO2 in the denominator
[HCO3−] in the numerator
pKa in the exponent
log base in the numerator
Given pH = pKa + log([HCO3−]/(S × pCO2)), which primary change raises blood pH?
Increased plasma bicarbonate concentration
Increased solubility constant of water
Increased arterial pCO2 pressure
Decreased log base ten constant
At steady state, the normal extracellular ratio for bicarbonate buffer is approximately
[HCO3−] : [H2CO3] = 20 : 1
[HCO3−] : [H2CO3] = 1 : 20
[HCO3−] : [H2CO3] = 10 : 1
[HCO3−] : [H2CO3] = 1 : 10
Which statement correctly links dissolved CO2 with its measurement in blood?
Dissolved CO2 concentration is proportional to pCO2
Dissolved CO2 concentration is independent of pCO2
Dissolved CO2 equals bicarbonate at all times
Dissolved CO2 is measured as oxygen tension
If arterial pCO2 acutely increases while bicarbonate remains constant, what immediate pH change occurs?
pH decreases because denominator increases
pH increases because numerator increases
pH unchanged because pKa compensates
pH increases because carbonic acid decreases
Which component is primarily regulated by the kidneys over hours to days in this buffer system?
Plasma bicarbonate concentration
Alveolar ventilation rate
Solubility constant S
Hemoglobin oxygen saturation
Which change most directly represents respiratory compensation for metabolic acidosis?
Decreased pCO2 via hyperventilation
Increased bicarbonate reabsorption
Increased solubility constant
Decreased strong ion difference
Using pH = pKa + log([HCO3−]/(S × pCO2)), pKa is best interpreted as
The dissociation constant of carbonic acid
The partial pressure of dissolved CO2
The activity coefficient of bicarbonate
The pH of normal arterial blood
Which pair correctly matches variable and typical value used in calculations?
Normal arterial pCO2 ≈ 40 mmHg
Normal arterial pCO2 ≈ 20 mmHg
Solubility constant S ≈ 1.0 mmol/L·mmHg
pKa for carbonic acid ≈ 9.4 at 37°C
In the diagram, which immediate respiratory change helps correct alkalosis by increasing carbonic acid formation?
Decreased respiratory rate raising arterial PCO2
Increased respiratory rate lowering arterial PCO2
Unchanged ventilation maintaining constant arterial PCO2
Breath-holding followed by deep hyperventilation
According to the bicarbonate buffer mechanism shown, what direct effect does renal handling have during alkalosis?
Secretion of bicarbonate into urine to reduce plasma HCO3−
Reabsorption of bicarbonate to expand the bicarbonate reserve
Secretion of hydrogen ions to acidify plasma rapidly
Generation of carbon dioxide to drive hyperventilation
A patient presents with lightheadedness after panic-induced hyperventilation. Using the diagram’s pathways, which combined adjustment best restores plasma pH?
Slow ventilation and release H+ from buffers
Increase ventilation and reabsorb HCO3− renally
Maintain ventilation and excrete H+ in urine
Induce hypoventilation and generate new HCO3−
Which buffer pair primarily maintains extracellular pH in plasma under physiological conditions?
Hemoglobin and Hb− in erythrocytes
Protein and Prot− in intracellular fluid
Phosphate H2PO4−/HPO4^2− system
Bicarbonate H2CO3/HCO3− system
Where is the hemoglobin buffer system’s main site of buffering action in the body?
Interstitial space of tissues
Erythrocytes within blood
Renal tubular lumen
Hepatic extracellular fluid
Which buffer system is most effective within cells for titrating metabolic acids at physiological pH?
Bicarbonate buffer in extracellular fluid
Phosphate buffer in intracellular fluid
Carbonic anhydrase within plasma
Ammonia buffer in interstitial fluid
A sudden rise in carbonic acid occurs in plasma. Which reaction best represents the immediate buffering response by plasma proteins?
H+ + Protein ⇌ H–Protein
CO2 + H2O ⇌ H2CO3
H2PO4−⇌HPO42−+H+
HbO2 ⇌ Hb− + O2
Which change most directly leads to respiratory acidosis under hypoventilation?
Increased CO2 raises carbonic acid lowering pH
Decreased CO2 lowers carbonic acid raising pH
Increased bicarbonate buffers acid raising pH
Decreased bicarbonate reduces buffering raising pH
The kidneys primarily regulate blood pH by which paired processes?
Bicarbonate reabsorption and hydrogen ion excretion
Carbonic acid formation and CO2 exhalation control
Oxygen uptake and carbon dioxide diffusion rate
Water reabsorption and sodium secretion balance
Which statement best compares compensation timescales of lungs and kidneys?
Lungs act within minutes, kidneys act hours to days
Lungs act hours to days, kidneys act within minutes
Both lungs and kidneys act within seconds equally
Both lungs and kidneys act over weeks typically
A patient hyperventilates for several minutes. Which immediate acid–base change is expected before renal compensation?
CO2 decreases causing pH to increase
CO2 increases causing pH to decrease
Bicarbonate increases causing pH to increase
Bicarbonate decreases causing pH to decrease
Metabolic alkalosis is most directly characterized by which primary disturbance?
Increased bicarbonate with elevated pH
Decreased bicarbonate with reduced pH
Increased CO2 with reduced pH
Decreased CO2 with elevated pH
Which ratio helps maintain an arterial pH near 7.4 under normal conditions?
Bicarbonate to carbonic acid of twenty to one
Bicarbonate to carbonic acid of one to one
Carbonic acid to bicarbonate of ten to one
Carbon dioxide to bicarbonate of five to one
A patient presents with low pH and low CO2 after several hours of compensatory breathing. Which primary disorder best fits?
Metabolic acidosis with respiratory compensation
Metabolic alkalosis with respiratory compensation
Respiratory acidosis with renal compensation
Respiratory alkalosis with renal compensation
Which blood pH range is labeled as normal in the diagram?
7.00 to 7.20
7.35 to 7.45
7.45 to 7.60
7.80 to 8.00
8.50 to 9.00
In the bicarbonate buffer diagram, which variable represents the respiratory component affecting blood pH?
[HCO3−] concentration
pCO2 partial pressure
Base excess value
Plasma sodium level
Oxygen saturation percent
A patient has blood pH of 7.28. Based on the diagram ranges, which condition is most consistent?
Severe alkalosis likely
Normal acid–base status
Acidosis likely present
Compensated alkalosis
Incompatible with life
According to the bicarbonate buffer relationship pH ∼ [HCO3−]/pCO2, which change would most directly raise blood pH?
Decrease [HCO3−] by kidneys
Increase pCO2 via hypoventilation
Increase [HCO3−] via renal reabsorption
Increase lactic acid production
Decrease oxygen binding affinity
If hypoventilation elevates pCO2 while kidney function is unchanged, what is the predicted pH direction?
pH will increase modestly
pH will decrease initially
pH will remain unchanged
pH will oscillate randomly
pH will exceed 7.80
Which expression represents the Henderson–Hasselbalch equation for blood pH using bicarbonate and pCO2?
pH = pKa + log([HCO3−]/(S × pCO2))
pH = pKa − log(S × [HCO3−] × pCO2)
pH = pKa + log(S × pCO2/[HCO3−])
pH = pKa − log([HCO3−]/(S × pCO2))
The dissociation constant term in the blood Henderson–Hasselbalch equation for carbonic acid is closest to which value?
6.1 units on the pH scale
7.0 units on the pH scale
6.8 units on the pH scale
7.4 units on the pH scale
If plasma bicarbonate concentration rises while pCO2 remains constant, what is the expected effect on blood pH?
Increase toward metabolic alkalosis
Decrease toward metabolic acidosis
No change from respiratory effects
Oscillate with respiratory compensation
Normal arterial pCO2 is approximately which value used in calculations?
40 mmHg in typical adults
60 mmHg in healthy adults
30 mmHg in resting adults
50 mmHg in awake adults
In the term S × pCO2 within the Henderson–Hasselbalch equation for blood, what does S represent?
Solubility constant of CO2 in plasma
Stoichiometric coefficient for carbonic acid
Standard slope for titration in plasma
Saturation constant for hemoglobin binding
A patient hypoventilates, causing pCO2 to rise while bicarbonate is unchanged acutely. Using the equation, which acid–base disturbance initially develops?
Respiratory acidosis with lower pH
Respiratory alkalosis with higher pH
Metabolic alkalosis with higher pH
Metabolic acidosis with lower pH
Two patients have the same bicarbonate and pCO2 values multiplied by the solubility constant, but different absolute amounts of CO2 in the blood. What best explains their identical pH values?
pH depends on the ratio of bicarbonate to dissolved CO2
pH is fixed by total body CO2 content
pH follows absolute bicarbonate concentration
pH is determined by alveolar ventilation only
Which range best represents normal arterial blood pH in healthy adults?
7.00 to 7.20
7.35 to 7.45
7.50 to 7.70
6.80 to 7.00
Arterial blood pH of 7.28 most likely indicates which condition?
Physiologic alkalosis
Severe alkalemia
Acidemia consistent with acidosis
Normal acid-base state
In primary respiratory acidosis, which primary change is expected before compensation?
Decrease in PaCO2
Increase in PaCO2
Decrease in HCO3−
Increase in blood pH
Which pattern best matches metabolic alkalosis before compensation?
pH < 7.35 with PaCO2 > 40 mmHg
pH > 7.40 with HCO3− > 24 mEq/L
pH > 7.40 with PaCO2 < 40 mmHg
pH < 7.35 with HCO3− < 24 mEq/L
A patient has pH 7.50, PaCO2 30 mmHg, and HCO3− 22 mEq/L. Which primary disorder is most consistent?
Respiratory alkalosis
Metabolic alkalosis
Metabolic acidosis
Respiratory acidosis
Which statement about compensation is most accurate?
Respiratory compensation adjusts HCO3− rapidly
Renal compensation alters PaCO2 within minutes
Respiratory compensation changes PaCO2 to offset pH
Neither respiratory nor renal systems affect pH
Which survival range for arterial pH is commonly depicted in the diagrams?
7.8 to 8.2 only
6.8 to 7.8 approximately
6.0 to 8.5 broadly
7.2 to 7.6 narrowly
Given pH 7.30 and HCO3− 18 mEq/L with PaCO2 30 mmHg, which interpretation fits best?
Primary metabolic acidosis with respiratory compensation
Primary respiratory acidosis with renal compensation
Primary metabolic alkalosis with renal compensation
Primary respiratory alkalosis with renal compensation
According to the balance-scale diagram, which primary change defines respiratory acidosis?
Increase in pCO2 causing decreased blood pH
Decrease in pCO2 causing increased blood pH
Decrease in bicarbonate causing decreased blood pH
Increase in bicarbonate causing increased blood pH
Which statement best defines alkalosis as shown in the diagram?
A process resulting in increased blood pH
A process resulting in decreased blood pH
A process resulting in stable blood pH
A process resulting in unchanged hydrogen ions
A primary decrease in plasma bicarbonate is most consistent with which disorder on the diagram?
Metabolic acidosis due to lower bicarbonate
Metabolic alkalosis due to lower bicarbonate
Respiratory acidosis due to lower bicarbonate
Respiratory alkalosis due to lower bicarbonate
A patient hyperventilates, producing a primary fall in pCO2. Using the diagram’s logic, predict the acid–base disturbance.
Respiratory alkalosis with higher blood pH
Respiratory acidosis with lower blood pH
Metabolic acidosis with lower blood pH
Metabolic alkalosis with higher blood pH
Which primary change defines metabolic acidosis?
Decrease in plasma bicarbonate
Increase in plasma bicarbonate
Increase in arterial pCO2
Decrease in arterial pCO2
What is the immediate compensatory response to metabolic acidosis?
Hyperventilation lowering pCO2
Hypoventilation raising pCO2
Renal bicarbonate reabsorption
Renal bicarbonate secretion
Which acid-base disorder primarily features increased plasma bicarbonate?
Metabolic alkalosis
Metabolic acidosis
Respiratory acidosis
Respiratory alkalosis
In respiratory acidosis, which compensatory change occurs over time?
Renal bicarbonate generation increases
Renal bicarbonate generation decreases
Alveolar ventilation acutely increases
Plasma bicarbonate acutely decreases
Which compensation mainly requires days rather than minutes to develop fully?
Renal bicarbonate adjustments
Hyperventilation responses
Hypoventilation responses
Buffering by intracellular proteins
A patient has low pCO2 with alkalemia. Which compensatory mechanism best fits respiratory alkalosis?
Renal bicarbonate reabsorption decreases
Renal bicarbonate reabsorption increases
Ventilatory drive decreases chronically
Plasma bicarbonate increases promptly
Which statement best contrasts compensations for metabolic versus respiratory disturbances?
Metabolic changes trigger respiratory responses within minutes
Metabolic changes trigger renal responses within minutes
Respiratory changes trigger respiratory responses within days
Respiratory changes trigger ventilatory responses within hours
A patient with vomiting develops elevated plasma bicarbonate. What is the expected acute respiratory compensation?
Hypoventilation raising arterial pCO2
Hyperventilation lowering arterial pCO2
Renal secretion of bicarbonate immediately
No change in ventilation expected
Which condition is a typical cause of metabolic acidosis due to increased organic acids in blood?
Diabetes mellitus causing ketoacidosis
Hyperventilation during acute anxiety
Vomiting with persistent gastric losses
Intravenous bicarbonate after resuscitation
Chronic obstructive airway hyperinflation
A patient with severe diarrhea develops acid-base disturbance primarily from loss of bicarbonate. Which disorder is most likely?
Metabolic acidosis from bicarbonate loss
Respiratory acidosis from CO2 retention
Metabolic alkalosis from hydrogen loss
Respiratory alkalosis from hyperventilation
Mixed alkalosis from renal compensation
Which scenario best matches a cause of respiratory acidosis?
Airway obstruction impairing CO2 excretion
Vomiting leading to hydrogen ion loss
Hyperventilation during high fever
Intravenous bicarbonate administration
Renal tubular acidosis type one
Failure of respiratory muscles, such as in multiple sclerosis, most directly leads to which acid–base disorder?
Respiratory acidosis from hypoventilation
Metabolic alkalosis from bicarbonate gain
Respiratory alkalosis from hyperventilation
Metabolic acidosis from lactate excess
Mixed acidosis from renal bicarbonate loss
Which is a common trigger for metabolic alkalosis related to gastrointestinal losses?
Nasogastric suction removing stomach acid
Cardiac arrest reducing tissue perfusion
Severe asthma increasing air trapping
Anemia causing tissue hypoxia
Renal failure retaining inorganic acids
Which listed factor is classically associated with respiratory alkalosis?
Hyperventilation due to anxiety or fever
Depression of the respiratory center
Airway obstruction with mucus plugging
Chest wall deformities restricting lungs
Cardiac arrest with hypoperfusion
Renal failure leading to retention of inorganic acids most likely produces which disturbance?
Metabolic acidosis with acid accumulation
Respiratory alkalosis with low pCO2
Metabolic alkalosis with base excess
Respiratory acidosis with CO2 retention
Mixed disorder with normal pH unchanged
Which medication-related scenario can precipitate respiratory acidosis?
Opiate-induced depression of respiratory center
Aspirin-induced respiratory stimulation early
Loop diuretic causing metabolic alkalosis
Bicarbonate bolus after cardiac arrest
Insulin therapy reducing ketoacidosis
A patient with hypokalemia is at risk of which acid–base disorder according to common causes?
Metabolic alkalosis promoted by low potassium
Respiratory acidosis from hypoventilation
Metabolic acidosis from bicarbonate loss
Respiratory alkalosis from hyperventilation
Mixed acidosis with lactate accumulation
Which is a recognized cause of respiratory alkalosis linked to toxins?
Salicylate poisoning stimulating ventilation
Opiate overdose depressing ventilation
Carbon monoxide impairing oxygen delivery
Ethanol intoxication increasing lactate
Organophosphate crisis causing muscle weakness
Which test is the primary diagnostic tool for acid–base disorders in clinical practice?
Arterial blood gas analysis
Complete blood count panel
Basic metabolic panel test
Urinalysis with microscopy
A patient’s ABG shows pH 7.30, pCO2 42 mmHg, and HCO3− 20 mEq/L. What is the primary disturbance?
Metabolic acidosis without compensation
Respiratory acidosis without compensation
Metabolic alkalosis with compensation
Respiratory alkalosis with compensation
Which parameter in ABG interpretation primarily reflects the respiratory component of acid–base status?
pCO2 level in mmHg
HCO3− level in mEq/L
Serum sodium concentration
Anion gap calculation
Normal ABG reference ranges are listed for several variables. Which set is correct?
pH 7.35–7.45, pCO2 35–45, HCO3− 22–26
pH 7.25–7.55, pCO2 25–35, HCO3− 18–22
pH 7.30–7.50, pCO2 30–40, HCO3− 20–24
pH 7.40–7.60, pCO2 40–55, HCO3− 26–30
Place the steps of ABG interpretation in the most logical order for accuracy.
Assess pH, determine cause, judge compensation
Judge compensation, assess pH, determine cause
Determine cause, judge compensation, assess pH
Assess pH, judge compensation, determine cause
A pH of 7.48 with a pCO2 of 30 mmHg and an HCO3− of 23 mEq/L most likely indicates which disturbance?
Primary respiratory alkalosis
Primary metabolic alkalosis
Metabolic acidosis with compensation
Respiratory acidosis with compensation
Which ABG finding best supports metabolic alkalosis as the primary problem?
Elevated HCO3− with alkaline pH
Elevated pCO2 with acidic pH
Low HCO3− with acidic pH
Low pCO2 with alkaline pH
Which specimen is standard for arterial blood gas analysis in adults?
Arterial blood from radial artery
Venous blood from cubital vein
Capillary blood from fingertip
Mixed venous blood from catheter
Which parameter is directly measured in a routine arterial blood gas panel?
pH, pCO2, pO2
Bicarbonate by enzymatic assay
Base excess by titration
Buffer base by electrophoresis
Which arterial reference range for pH is correct for a healthy adult at sea level?
7.35 to 7.45
7.30 to 7.38
7.45 to 7.55
7.20 to 7.30
An arterial pCO2 of 6.4 kPa (48 mmHg) with normal bicarbonate most likely indicates which primary disturbance?
Primary respiratory acidosis
Primary metabolic acidosis
Primary respiratory alkalosis
Primary metabolic alkalosis
A patient’s arterial values are pH 7.28, pCO2 4.8 kPa (36 mmHg), bicarbonate 17 mmol/L. Which interpretation best fits these data?
residually balanced?
Uncompensated metabolic acidosis
Acute respiratory acidosis
Chronic metabolic alkalosis
According to the diagram, which pH value is within the normal range for arterial blood?
7.28
7.36
7.52
7.20
A patient’s PaCO2 is 48 mmHg. Using the visual scale, this value most directly indicates a shift toward which condition?
Respiratory alkalosis tendency
Respiratory acidosis tendency
Metabolic alkalosis tendency
Metabolic acidosis tendency
The diagram lists a normal HCO3 range of 22–26 mEq/L. Which interpretation best matches an HCO3 of 19 mEq/L when pH is decreased?
Consistent with metabolic alkalosis
Consistent with metabolic acidosis
Unrelated to acid–base status
Indicates primary respiratory disorder
A 47-year-old with prolonged vomiting has ABG: pH 7.55, pCO2 6.4 kPa, HCO3− 35 mmol/L. Which primary disorder best fits these values?
Respiratory alkalosis with renal compensation
Metabolic alkalosis with respiratory compensation
Respiratory acidosis with metabolic compensation
Metabolic acidosis with respiratory compensation
Prolonged vomiting most directly causes which change leading to the diagnosed acid–base disorder in this patient?
Loss of bicarbonate in gastrointestinal secretions
Retention of carbon dioxide due to hypoventilation
Loss of gastric hydrochloric acid from the stomach
Increased lactic acid production during hypoperfusion
A 56-year-old with chronic bronchitis presents with pCO2 8.4 kPa, pO2 6 kPa, pH 7.35, and bicarbonate 35 mmol/L. Which interpretation best fits these arterial blood gases?
Acute respiratory acidosis without compensation
Chronic respiratory acidosis with metabolic compensation
Primary metabolic acidosis with respiratory compensation
Primary metabolic alkalosis from volume depletion
Mixed respiratory alkalosis and metabolic acidosis
In COPD-related respiratory acidosis, why should high-flow oxygen be given cautiously to this patient?
It decreases alveolar ventilation via hypercapnic drive
It increases bicarbonate loss through renal mechanisms
It may reduce hypoxic drive causing respiratory depression
It directly lowers blood pH causing severe acidosis
It raises pCO2 by accelerating anaerobic metabolism
