Chapter 26: Fluid, Electrolyte, and Acid-Base Balance (Mastering)
Which of the following statements is FALSE regarding water intake and output by the body?
An increase in the amount of beverages taken by mouth would increase the urine output.
An increase in fluid taken by mouth would reduce the amount produced by metabolism.
An irritation to the colon that leads to diarrhea would increase the proportion of water lost through feces.
The proportion of fluid lost by the body as sweat would increase during exercise.
An increase in fluid taken by mouth would reduce the amount produced by metabolism.
What hormone helps to maintain correct extracellular fluid (ECF) osmolality when concentrations become too high?
antidiuretic hormone (ADH)
aldosterone
angiotensin II
parathyroid hormone (PTH)
antidiuretic hormone (ADH)
What type of water imbalance increases the amount of fluid in all compartments?
dehydration
hypotonic hydration
inflammation
edema
hypotonic hydration
Which of the following conditions promotes edema?
diabetes mellitus
hemorrhage
hyponatremia
hypoproteinemia
hypoproteinemia
What negatively charged ion is reabsorbed by renal tubules when the blood pH is drawing near its alkaline limit?
NO2 -
Cl-
PO4 -3
HCO3 -
Cl-
Which of the following would NOT be associated with a rise in K+ concentration in the extracellular fluid (ECF)?
a drop in Na+ reabsorption
a rise in K+ excretion
release of aldosterone
stimulation of the adrenal cortex
a drop in Na+ reabsorption
Of the three buffering mechanisms in the body, which is the strongest?
chemical buffer system
renal system
respiratory system
renal system
The bicarbonate buffer system is one of the chemical buffer systems of the body. How would the bicarbonate buffer system work if sodium hydroxide were added to a solution?
The hydrogen ion would attach to carbonic acid.
A hydrogen on carbonic acid would dissociate and join the hydroxyl group on the base to form water and sodium bicarbonate.
The hydrogen ion would attach to bicarbonate (HCO3) to form carbonic acid (H2CO3).
A hydrogen on carbonic acid would dissociate and join the hydroxyl group on the base to form water and sodium bicarbonate.
The respiratory system is one of the three systems that regulate acid-base balance in the body. How does it work to decrease an acidosis?
Carbonic acid is broken down into water and CO2; the CO2 is then exhaled.
Carbonic acid is converted to bicarbonate and hydrogen ions.
Carbonic acid is converted to bicarbonate, which then buffers the acid.
Carbonic acid converts a strong acid to a weak acid, thus decreasing acidity.
Carbonic acid is broken down into water and CO2; the CO2 is then exhaled.
In a respiratory acidosis the kidney would do which of the following?
The kidney would reabsorb bicarbonate and secrete hydrogen ions.
The kidney will reabsorb both bicarbonate and hydrogen ions.
When it reabsorbs the hydrogen ion, it also generates more bicarbonate ions.
The kidney would increase excretion of both bicarbonate and hydrogen ions.
The kidney would reabsorb bicarbonate and secrete hydrogen ions.
Ingesting too much antacid would cause which of the following acid-base disturbances?
metabolic acidosis
respiratory alkalosis
metabolic alkalosis
respiratory acidosis
metabolic alkalosis
Vomiting will cause which type of acid-base disturbance?
metabolic acidosis
metabolic alkalosis
respiratory acidosis
respiratory alkalosis
metabolic alkalosis
Severe anxiety would cause which type of acid-base disturbance? What would be the compensation?
respiratory alkalosis; kidneys would excrete HCO3
respiratory alkalosis; kidneys would retain HCO3
respiratory acidosis; kidneys would excrete HCO3
metabolic alkalosis; hypoventilation by the lungs
respiratory alkalosis; kidneys would excrete HCO3
What is the most important trigger for aldosterone release?
increased osmolality of the extracellular fluids (ECF)
decreased sodium ion concentration in the extracellular fluids (ECF)
renin-angiotensin-aldosterone mechanism
decreased K+ concentration in the extracellular fluids (ECF)
renin-angiotensin-aldosterone mechanism
Which of the following does NOT impact how much sodium is reabsorbed?
atrial natriuretic peptide
estrogen
transport maximum of the renal proximal tubule
aldosterone
transport maximum of the renal proximal tubule
Which of the following is NOT an effect of PTH?
increase Ca2+ reabsorption in the kidneys
to decrease Ca+ absorption in the gut
to activate osteoclasts
promotes activation of vitamin D by the kidneys
to decrease Ca+ absorption in the gut
Hypersecretion of aldosterone results in hypokalemia, which causes hyperpolarization of neurons; this in turn results in ______.
increased speed of sodium-potassium pump activity in order to compensate for the reduced concentration of potassium ions
decreased plasma membrane permeability to potassium ions
the need for a stronger than normal stimulus in order to trigger an action potential
a craving for more salt in the diet
the need for a stronger than normal stimulus in order to trigger an action potential
Which of the following is the only logical explanation for why hypocalcemia increases neuromuscular excitability and causes muscle tetany?
Low plasma calcium ion concentration decreases the release of calcium ions from the sarcoplasmic reticulum.
Low plasma calcium ion concentration decreases the rate of exocytosis of synaptic vesicles.
Low plasma calcium ion concentration increases the permeability of neuron membranes to sodium ions, thereby causing depolarization that in turn increases the likelihood of action potentials being generated.
Low plasma calcium ion concentration increases the likelihood of acetic acid and choline being formed in the synaptic cleft when a neuron is stimulated to the threshold level.
Low plasma calcium ion concentration increases the permeability of neuron membranes to sodium ions, thereby causing depolarization that in turn increases the likelihood of action potentials being generated.
What is the primary buffer in the plasma?
sodium-potassium buffer system
bicarbonate buffer system
protein buffer system
phosphate buffer system
bicarbonate buffer system
An increase in blood CO2 levels leads to __________.
a decrease in carbonic acid
an increase in blood pH
a decreased respiratory rate
a drop in blood pH
a drop in blood pH