Ch. 27 Fluid Electrolyte and Acid-Base Balance

Why is there a difference in the ICF percentages in males versus females?

Greater water content of muscle tissue versus adipose tissue

What would be the effect on the osmotic concentration of blood plasma if you were in the desert without water for a day?

The osmotic concentration of your plasma would increase because of water leaving your body.

In a protein buffer system, if the pH increases, the carboxyl group (COOH) of the amino acid dissociates and releases __________.

a hydrogen ion

What effect does prolonged sweating have on sodium ion levels?

a loss of sodium ions from the ECF

If the partial pressure of CO2 rises in the blood, which of the following happens? a. A decrease in pH b. A decrease in H+ concentration c. A decrease in HCO3- concentration d. An increase in pH

a. A decrease in pH

Which of the following is true regarding antidiuretic hormone (ADH) and its role in regulating fluid and electrolyte balance? a. ADH stimulates water conservation by the kidneys and helps to concentrate the urine. b. ADH is produced in the posterior pituitary and is released in response to high osmotic concentrations. c. ADH is released from fenestrated capillaries in the anterior pituitary. d. Increased ADH inhibits the hypothalamic thirst centers.

a. ADH stimulates water conservation by the kidneys and helps to concentrate the urine.

Important homeostatic adjustments occur in response to changes in __________.

plasma volume or osmolarity

What is the most abundant cation in the ICF?

potassium

The p in pH refers to

power

The primary role of the carbonic acid−bicarbonate buffer system is to __________.

prevent changes in pH caused by metabolic and fixed acids in the ECF

A metabolic alkalosis can be due to

prolonged vomiting

Which component makes up the largest portion of the solid components in the body?

proteins

A mismatch between carbon dioxide generation in peripheral tissues and carbon dioxide excretion at the lungs is a __________.

respiratory acid-base disorder

Hypercapnia, or an elevation of carbon dioxide in the blood, is a sign of __________.

respiratory acidosis

Osmosis allows water to freely cross plasma membranes except in the _____________.

ascending limb of the nephron loop

After a person consumes a meal, the levels of which ion rises in the blood in response to increased acid production in the stomach?

bicarbonate

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

Chronic diarrhea causes a severe loss of bicarbonate ions, resulting in

metabolic acidosis

What is the term for a substance that opposes a change in pH in a solution and can either remove or replace hydrogen ions?

buffer

An abnormally high level of which electrolyte could be caused by hyperparathyroidism and would result in kidney stones, confusion, muscle pain, and cardiac arrhythmias?

calcium

A fluid shift of abnormally large amounts of water from the plasma into the interstitial fluid is called __________.

edema

Water, by far, is the biggest component of our body fluids. What is the second-largest component of our body fluids?

electrolytes

Hyperventilation causes

respiratory alkalosis

What is required for the body to be in acid-base balance?

the production of hydrogen ions is exactly offset by their losses

The concentrations of the cations and anions in the ICF and ECF are measured in terms of milliequivalent per liter (mEq/L). mEq/L represents the _________________.

total number of positive and negative electrical charges in a liter of solution

Which of the following is NOT a response in the regulation of acute respiratory acidosis?

HCO3- ions are secreted into the urine

What is the most abundant cation in the ECF?

Sodium

When water losses outpace water gains, __________ occurs.

dehydration

When a normal pulmonary response does NOT reverse respiratory acidosis, the kidneys respond by __________.

increasing the rate of hydrogen ion secretion into the tubular fluid

What would happen if you ate a large quantity of salty potato chips without drinking anything?

secretion of ADH would increase

What is the kidney's response to acidosis?

secretion of H+ into urine

A pH below ____ or above _____ is not sustainable for life.

6.8; 7.7

What is the normal pH of the ECF?

7.35-7.45

What is an electrolyte?

Ions released through the dissociation of inorganic compounds

A patient presents with a blood pH of 7.5, a PCO2 of 32, and a normal HCO3-. What is the likely cause of this patient's abnormal lab values?

Panic attacks causing acute respiratory alkalosis

What is meant by the term metabolic water?

Water generated during oxidative phosphorylation

As a result of the aging process, the ability to regulate pH through renal compensation changes due to __________.

a reduction in the number of functional nephrons

The elderly have an increased risk of respiratory acidosis because of __________.

a reduction in vital capacity

Which of the following is the best way of describing respiratory compensation? a. A change in the respiratory rate that helps stabilize the pH of the ECF. b. A change in the respiratory rate that helps stabilize the pH of the ICF. c. A change in the rates of H+ and HCO3- secretion or reabsorption by the kidneys in response to changes in the plasma pH. d. The homeostatic interplay between the urinary and respiratory systems to maintain blood pH.

a. A change in the respiratory rate that helps stabilize the pH of the ECF

Which of the following is not consistent with rising CO2 levels? a. Additional Na+ ions are released. b. Additional H+ ions are produced. c. Additional bicarbonate ions are produced. d. Blood pH decreases.

a. Additional Na+ ions are released.

Which of the following hormones causes the conservation of sodium in the kidneys? a. Aldosterone b. Antidiuretic hormone c. Natriuretic peptide d. Calcitonin

a. Aldosterone

Which of the following accurately describes the role of aldosterone in fluid and electrolyte balance? a. Aldosterone is secreted in response to an increasing K+ or decreasing Na+ level in the blood. b. The higher the concentration of aldosterone, the more efficiently the kidneys release sodium in the urine. c. Aldosterone release is inhibited by the release of renin. d. The higher the concentration of aldosterone, the more efficiently the kidneys release chloride ions in the urine.

a. Aldosterone is secreted in response to an increasing K+ or decreasing Na+ level in the blood.

Which of the following is a cause of a fluid shift? a. All of the listed choices are causes of a fluid shift. b. Excessive sweating c. Drinking a large volume of water d. Diarrhea

a. All of the listed choices are causes of a fluid shift.

What would be the response of the body to an increase in ECF volume if you were to drink a large quantity of a sports drink? a. All of the listed choices are correct. b. Natriuretic peptides would be released by cardiac muscle cells. c. Increased water and sodium loss in the urine d. Decreased thirst

a. All of the listed choices are correct.

Why must tubular fluid in the nephron be buffered? a. All of the listed choices are correct. b. To keep H+ from diffusing back into the blood c. To allow secretion of H+ to continue d. To prevent the pH of the urine from becoming too low

a. All of the listed choices are correct.

Why is it more likely for an older person to become dehydrated? a. All of the the listed choices are correct. b. Water content is reduced with age. c. Ability to concentrate the urine decreases with age. d. Reduction in sensitivity to ADH and aldosterone with age

a. All of the the listed choices are correct.

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

What is the term for an abnormally high concentration of sodium in the ECF?

hypernatremia

What is the term for an abnormally low concentration of potassium in the blood?

hypokalemia

The body content of water will rise if __________.

intake exceeds outflow

The loss of mineral content with age is frequently due to what cause?

loss of muscle and bone mass

Who would have the highest percentage of water content?

male infant

A loss of bicarbonate ions can lead to

metabolic acidosis

Given the following data, what would be your diagnosis for this patient? Data: pH 7.32; PCO2 38; HCO3- 20 mEq/L

metabolic acidosis

A loss of H+ or a gain in HCO3- can lead to

metabolic alkalosis

Prolonged vomiting and loss of stomach acid causes

metabolic alkalosis

The effects of both respiratory acidosis and metabolic acidosis are especially serious in cases of

near drowning

Fluid and electrolyte balance is maintained by receptors that directly measure _________.

overall osmotic concentration

What are the principal ions in the extracellular fluid (ECF)?

sodium, chloride, and bicarbonate

Ketone bodies accumulate in the blood during are associated with __________.

starvation

The hemoglobin buffer system helps prevent drastic alterations in pH when __________.

the plasma PCO2 is rising or falling

Blood pH is normally between __________.

7.35-7.45

Given the following data, what would be your diagnosis for this patient? Data: pH 7.3; pCO2 51 mm Hg.; HCO3- 31 mEq/L

Respiratory acidosis

Which of the following is not accurate regarding the generation of ammonia within kidney tubules? a. Ammonia is broken down by carbonic anhydrase to form ammonium ions. b. Ammonium ions (NH4+) are transported into the tubule lumen and are exchanged for Na+ in the tubular fluid. c. Ammonia (NH3) is toxic to cells and rapidly diffuses into tubular fluid where it reacts with H+ to form NH4+. d. Tubule cells use glutaminase to break down the amino acid glutamine, which creates either ammonium ions or ammonia as a product.

a. Ammonia is broken down by carbonic anhydrase to form ammonium ions.

Acidosis is a more common problem than alkalosis because many acids are the direct byproducts of metabolic reactions. Which of the following acids is not a metabolic acid? a. Carbonic acid b. Pyruvic acid c. Lactic acid d. Ketone bodies

a. Carbonic acid

Which of the following is a volatile acid and is a product of the combination of carbon dioxide and water? a. Carbonic acid b. Sulfuric acid c. Lactic acid d. Ketone bodies

a. Carbonic acid

Which buffer is the most important buffer in the extracellular fluid? a. Carbonic acid-bicarbonate buffer b. Hemoglobin buffer c. Phosphate buffer d. Amino acid buffer

a. Carbonic acid-bicarbonate buffer

Which of the following would not be associated with a sensation of increased thirst? a. Decrease in the production of ADH b. Increase in the production of angiotensin II c. Increase in renin secretion d. Increase in the production of ADH

a. Decrease in the production of ADH

Which of the following is NOT a cause of hyperkalemia? a. Decreased blood volume b. Chronically low blood pH c. Kidney damage or disease d. Some diuretics

a. Decreased blood volume

Which of the following is not a hormone that mediates adjustments to fluid balance and electrolyte balance? a. EPO b. ADH c. Aldosterone d. BNP

a. EPO

Acid is a natural byproduct of many metabolic processes. Which of the following does not contribute to an increase in H+? a. H+ is increased by expiration of CO2 by the lungs. b. H+ is increased by cellular respiraton. c. H+ is increased by the diet along the digestive tract. d. H+ is increased by muscle metabolism.

a. H+ is increased by expiration of CO2 by the lungs.

The major causes of metabolic acidosis include all of the following except? a. Hypercapnia b. Impaired ability to excrete H+ at the kidneys c. A severe bicarbonate loss d. Production of a large number of fixed or metabolic acids

a. Hypercapnia

Which of the following might be a response to respiratory acidosis? a. Increased respiratory rate b. Release of hydrogen ions by buffer systems c. Increased bicarbonate secretion in the kidneys d. Decreased respiratory rate

a. Increased respiratory rate

Which of the following is NOT an ECF? a. Intracellular fluid b. Lymph c. Cerebrospinal fluid d. Plasma

a. Intracellular fluid

Potassium ions are found in the highest concentrations in which of the following fluid compartments? a. Intracellular fluid (ICF) b. Blood plasma c. Cerebrospinal fluid (CSF) d. Lymph

a. Intracellular fluid (ICF)

Which of the following is NOT a principal ion in the extracellular compartments? a. Magnesium ion (Mg2+) b. Sodium (Na+) c. Chloride (Cl-) d. Bicarbonate (HCO3-)

a. Magnesium ion (Mg2+)

Homeostasis maintains a stable internal environment, composed of our body fluids. Which of the following is NOT one of the processes for stabilizing body fluid volumes? a. Nutrient balance b. Acid-base balance c. Electrolyte balance d. Fluid balance

a. Nutrient balance

Which of the following occurs when an individual loses body water? a. Plasma volume decreases, and electrolyte concentrations rise. b. Plasma volume increases, and electrolyte concentrations increase. c. Plasma volume increases, and electrolyte concentrations decrease. d. Plasma volume decreases, and electrolyte concentrations decrease.

a. Plasma volume decreases, and electrolyte concentrations rise

Which of the following accurately lists the solid components of the human body by weight from greatest to smallest? a. Proteins > lipids > minerals > carbohydrates b. Carbohydrates > minerals > lipids > proteins c. Proteins > minerals > lipids > carbohydrates d. Minerals > carbohydrates > proteins > lipids

a. Proteins > lipids > minerals > carbohydrates

Electrolyte balance requires matching the gain of electrolytes from your diet with the loss of electrolytes. Which of the following is NOT a way your body removes electrolytes? a. Respiration b. Urine production c. Sweating d. Defecation

a. Respiration

Which of the following descriptions is correct? a. Respiratory acid-base disorders result from a mismatch between CO2 generation in peripheral tissues and CO2 excretion by the lungs. b. In respiratory acid-base disorders, the CO2 levels of the ICF is abnormal. c. Metabolic acid-base disorders are caused by increasing the concentration of HCO3- in the ICF. d. Metabolic acid-base disorders are caused by the reduction of fixed acids and metabolic acids.

a. Respiratory acid-base disorders result from a mismatch between CO2 generation in peripheral tissues and CO2 excretion by the lungs

Which term is correctly matched up with its definition? a. Salt—an ionic compound consisting of a cation other than hydrogen and an anion other than a hydroxide ion b. Buffer—a substance that dissociates to release hydrogen ions, decreasing pH c. Neutral—a substance that tends to oppose changes in the pH of a solution by removing or replacing hydrogen ions in body fluids d. Acid—a substance that dissociates to release hydroxide ions or accept hydrogen ions, increasing pH

a. Salt—an ionic compound consisting of a cation other than hydrogen and an anion other than a hydroxide ion

Which of the following is NOT a source of water gains? a. Sensible perspiration b. Liquid c. Food d. Metabolism

a. Sensible perspiration

Which of the following is NOT a principal ion in the intracellular compartment? a. Sodium (Na+) b. Potassium (K+) c. Phosphate (HPO42-) d. Magnesium (Mg2+)

a. Sodium

Which of the following is NOT a buffer system in the ECF or ICF? a. Sulfate buffer system b. Carbonic acid−bicarbonate buffer system c. Protein buffer system d. Phosphate buffer system

a. Sulfate buffer system

Which of the following is a basic principle in understanding fluid and electrolyte balance? a. The body's content of water or electrolytes will increase if dietary gains exceed losses to the environment. b. All homeostatic mechanisms that respond and adjust the composition of body fluids respond to changes in the ICF, not in the ECF. c. Multiple receptors throughout the body directly monitor fluid or electrolyte levels. d. Cells move water by active transport.

a. The body's content of water or electrolytes will increase if dietary gains exceed losses to the environment.

Which of the following does not occur when the pH increases (become more basic)? a. The carboxylate ion can act as a weak base and accept additional H+ ions. b. The carboxyl group (-COOH) of the aminio acid can dissociate acting as a weak acid and releasing an H+. c. The carboxyl group can become a carboxylate in (-COO-), which adds to the overall negative charge of proteins. d. The R groups of histidine and cysteine will donate H+ ions.

a. The carboxylate ion can act as a weak base and accept additional H+ ions.

Which of the following is NOT a response during the regulation of metabolic alkalosis? a. The respiratory rate is increased. b. H+ ions are generated. c. HCO3- ions are secreted. d. Buffer systems other than carbonic acid-bicarbonate donate H+.

a. The respiratory rate is increased.

Which of the following represents the largest volume of water lost each day under normal physiological conditions? a. Urine b. Evaporation through the skin c. Feces d. Evaporation through the lungs

a. Urine

Which of the following is accurate regarding water content? a. Water makes up about 60 percent of the total body weight of an adult male. b. Adipose tissue is composed of approximately 75 percent water. c. Skeletal muscle tissue is composed of approximately 10 percent water. d. Men and women contain essentially the same percent body water.

a. Water makes up about 60 percent of the total body weight of an adult male.

Which of the following is NOT a basic principle for understanding fluid and electrolyte balance? a. Water moves into and out of cells by active transport. b. Homeostatic mechanisms respond to changes in the ECF. c. Water and electrolyte content in the body is a balance between intake and losses. d. No receptors exist for fluid and electrolyte balance.

a. Water moves into and out of cells by active transport.

Renin is released in response to all of the following except ____________. a. a decrease in K+ concentration in the renal circulation b. a decrease in plasma volume of blood pressure at the juxtaglomerular complex of the nephron c. a decrease in the osmotic concentration of tubular fluid at the distal convouluted tubule d. a decrease in Na+ concentration in the renal circulation

a. a decrease in K+ concentration in the renal circulation

Angiotensin II produces a coordinated elevation in the extracellular fluid volume by all of the following mechanisms except __________. a. causing the release of ADH b. decreasing sodium loss in urine c. triggering the secretion of aldosterone d. stimulating thirst

a. causing the release of ADH

Extracellular fluids in the body consist of all of the following except __________. a. cytosol b. cerebrospinal fluid c. aqueous humor d. lymph

a. cytosol

Deviations outside of the normal pH range due to increases in hydrogen ion concentrations would do all of the following except __________. a. decrease the rate of respiration b. alter protein structure c. change the activities of important enzymes d. disrupt the stability of cell membranes

a. decrease the rate of respiration

Severe acidosis (blood pH below 7.0) can be deadly for all of the following reasons except _______________. a. hyperventilation leading to a lack of oxygen to critical tissues b. central nervous system function deteriorates and the person become comatose c. peripheral vasodilation produces a dramatic decrease in blood pressure, potentaily producing circulatory collapse d. cardiac contractions grow weak and irregular and signs of heart failure may develop

a. hyperventilation leading to a lack of oxygen to critical tissues

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