study area 27
In a protein buffer system, if the pH increases, the carboxyl group (COOH) of the amino acid dissociates and releases __________.
a hydrogen ion
As a result of the aging process, the ability to regulate pH through renal compensation changes as a result of __________.
a reduction in the number of functional nephrons
The elderly have an increased risk of respiratory acidosis because of ________
a reduction in vital capacity
The concentration of potassium in the ECF is controlled by adjustments in the rate of active secretion __________
along the distal convoluted tubule of the nephron
The most common problems with electrolyte balance are caused by _________
an imbalance between sodium gains and losses
Under normal circumstances, during respiratory acidosis the chemoreceptors monitoring the PCO2 of the plasma and CSF will eliminate the problem by calling for _________
an increase in pulmonary ventilation rates
After a person consumes a meal, the levels of which ion rise in the blood in response to increased acid production in the stomach?
bicarbonate
Sodium levels are figured as a balance between __________.
both absorption of sodium across the digestive epithelium and excretion at the kidney and other sites
Which of the following conditions could cause muscle cramps or spasms?
both hyperkalemia and hypocalcemia
Which of the following does NOT affect fluid levels in the blood?
chloride shift
Which of the following would NOT be associated with a sensation of increased thirst?
decrease in the production of ADH
Sodium ions enter the ECF by crossing the digestive epithelium via __________.
diffusion and active transport
All of the homeostatic mechanisms that monitor and adjust the composition of body fluids respond to changes in the __________.
extracellular fluid
When the amount of water you gain each day is equal to the amount you lose to the environment, you are in __________
fluid balance
If the ECF is hypertonic with respect to the ICF, water will move __________.
from the cells into the ECF until osmotic equilibrium is restored
When pure water is consumed, the extracellular fluid becomes __________.
hypotonic with respect to the ICF
When a normal pulmonary response does NOT reverse respiratory acidosis, the kidneys respond by _____
increasing the rate of hydrogen ion secretion into the filtrate
When water is lost but electrolytes are retained, the osmolarity of the ECF rises and osmosis then moves water __________.
out of the ICF and into the ECF until isotonicity is reached
Blood pH is normally measured at __________
pH 7.35-7.45
Important homeostatic adjustments occur in response to changes in __________.
plasma volume or osmolarity
The primary role of the carbonic acid-bicarbonate buffer system is to __________.
prevent changes in pH caused by organic and fixed acids in the ECF
A metabolic alkalosis can be due to _________
prolonged vomiting
What are the two important effects of increased release of ADH?
reduction of urinary water losses and stimulation of the thirst center
Which of the following does NOT cause hypokalemia?
renal failure
A mismatch between carbon dioxide generation in peripheral tissues and carbon dioxide excretion at the lungs is a __________.
respiratory acid-base disorder
What are the major contributors to the osmolarities of the ECF and the ICF?
sodium and potassium
What are the principal ions in the extracellular fluid (ECF)?
sodium, chloride, and bicarbonate
Ketone bodies accumulate in the blood during conditions of __________.
starvation
The hemoglobin buffer system helps prevent drastic alterations in pH when __________.
the plasma PCO2 is rising or falling
Chronic diarrhea causes a severe loss of bicarbonate ions, resulting in __________.
metabolic acidosis
The exchange between plasma and interstitial fluid is determined by the relationship between the _______
net hydrostatic and net colloid osmotic pressures
Normal ECF pH values are limited to the range between ______
7.35 and 7.45
Which of the following occurs when an individual loses body water?
Plasma volume decreases, and electrolyte concentrations rise.
The body content of water or electrolytes will rise if __________
intake exceeds outflow
Potassium ions are found in the highest concentrations in which of the following fluid compartments?
intracellular fluid (ICF)
Whenever the rate of sodium intake or output changes, there is a corresponding gain or loss of water that tends to __________.
keep the sodium concentration constant
Which of the following body organs has the greatest measure of control over body fluid and composition levels
kidneys
Increasing or decreasing the rate of respiration can have a profound effect on the buffering capacity of body fluids by __________.
lowering or raising the PCO2
Respiratory alkalosis develops when respiratory activity __________.
lowers plasma PCO2 to below-normal levels
