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