Deck 21: Water, Electrolyte, and Acid-Based Balance

Question 1

Intracellular fluids have high concentrations of

A) chloride and potassium ions.
B) sodium and phosphate ions.
C) potassium and phosphate ions.
D) sodium and chloride ions.

Answer 1

C

Question 2

Water balance and electrolyte balance are interdependent because

A) water dissolves in electrolytes.
B) water and electrolytes are both in an ionic state in the blood.
C) both form ions in blood.
D) electrolytes are dissolved in water.

Answer 2

D

Question 3

Marielle is very thirsty following her tennis game. She drinks for a few minutes, then stops. The stimulus to stop drinking comes from

A) distension of her stomach.
B) hormones secreted by stomach cells.
C) changes in intracellular fluid concentration.
D) changes in extracellular fluid concentration.

Answer 3

A

Question 4

The thirst center is located in the

A) thalamus.
B) hypothalamus.
C) midbrain.
D) medulla oblongata.

Question 5

Which is the largest compartment of extracellular water?

A) Plasma
B) Lymph
C) Interstitial fluid
D) Transcellular fluid

Question 6

A person in a moderate environment would lose the greatest volume of water in

A) sweat.
B) mucus.
C) feces.
D) urine.

Question 7

Compared to the average adult male, the average adult female has

A) more water and more adipose tissue.
B) more water and less adipose tissue.
C) less water and more adipose tissue.
D) less water and less adipose tissue.

Question 8

Water of metabolism is

A) water that a person drinks after exercising.
B) water that is in food.
C) a by-product of the oxidative metabolism of nutrients.
D) present only in adults.

Question 9

A person usually drinks about ____ milliliters a day.

A) 500
B) 1,000
C) 1,500
D) 2,500

Question 10

Which of the following body compartments is correctly matched with its location in the body?

A) intracellular - all fluids outside cells
B) extracellular - fluid in tissue spaces, blood vessels, and lymphatic vessels
C) extracellular - fluid in cells
D) transcellular - between the lipid layers of cell membranes

Question 11

Thirst is triggered when total body water decreases by as little as

A) 1%.
B) 10%.
C) 25%.
D) 58%

Question 12

If excess water enters the body,

A) ADH release increases.
B) more water is reabsorbed from the renal tubules.
C) osmoreceptors in the brain swell.
D) the collecting duct becomes more permeable to water.

Question 13

Extracellular fluids have relatively

A) high sodium and low potassium ion concentrations.
B) high sodium and high potassium ion concentrations.
C) low sodium and low potassium ion concentrations.
D) low sodium and high potassium ion concentrations.

Question 14

Transcellular fluid includes the water and electrolytes in

A) the cerebrospinal fluid.
B) the aqueous and vitreous humors of the eyes.
C) the synovial fluid of the joints.
D) all of the above.

Question 15

The movement of water and electrolytes between fluid compartments is regulated primarily by

A) diffusion and osmosis.
B) hydrostatic pressure and osmotic pressure.
C) pinocytosis and phagocytosis.
D) active and passive transport.

Question 16

The hormone aldosterone promotes the

A) reabsorption of sodium ions.
B) secretion of sodium ions.
C) reabsorption of potassium ions.
D) secretion of calcium ions.

Question 17

The ratio of intracellular to extracellular fluids in the body of an average male is

A) 1:2
B) 2:1
C) 1:1
D) 3:2

Question 18

ADH level in nephrons regulates water output by causing

A) the glomerulus and proximal convoluted tubule to filter less or more water.
B) the glomerular capsule and nephron loop to absorb more or less water.
C) the distal convoluted tubule and collecting duct to reabsorb more or less water.
D) the distal convoluted tubule and collecting duct to reabsorb more or less sodium ions.

Question 19

Which of the following most closely represents the percentage of water by weight in an adult male?

A) 35%
B) 45%
C) 55%
D) 65%

Question 20

The thirst center in the hypothalamus is stimulated by _____ of the extracellular fluid, and is inhibited by _____.

A) an increase in the osmotic pressure; distension of the stomach by water
B) a decrease in the osmotic pressure; stimulation of osmoreceptors
C) a decrease in sodium ions; an increase in sodium ions
D) nerve impulses from the cerebrum; nerve impulses from the thalamus

Question 21

Acid-base buffers are the first line of defense against shifts in pH because

A) they occur closest to the skin.
B) they are slow and prolonged.
C) they occur in everyone.
D) they are fast.

Question 22

An important stimulus for the secretion of aldosterone is

A) rising potassium ion concentration.
B) falling potassium ion concentration.
C) rising sodium ion concentration.
D) rising calcium ion concentration.

Question 23

When sodium ions are reabsorbed in response to the action of aldosterone, potassium ions are

A) actively reabsorbed.
B) passively reabsorbed.
C) secreted.
D) reabsorbed.

Question 24

Alkalosis is a pH of arterial blood

A) below 7.35
B) above 7.35
C) below 7.45
D) above 7.45

Question 25

Maxwell has just finished a brutal 10 kilometer run. His body has

A) an increased production of carbonic acid and increased pH of body fluids.
B) an increased production of carbonic acid and decreased pH of body fluids.
C) a decreased production of carbonic acid, and increased pH of body fluids.
D) a decreased production of carbonic acid and decreased pH of body fluids.

Question 26

Ingestion of too much sodium bicarbonate to relieve indigestion may lead to

A) respiratory acidosis.
B) respiratory alkalosis.
C) metabolic acidosis.
D) metabolic alkalosis.

Question 27

A strong acid is one that _____ and an example is _____.

A) ionizes more completely; H₂CO₃
B) ionizes less completely; H₂SO₄
C) gives off less H⁺; H₃PO₄
D) ionizes more completely; HC1

Question 28

Symptoms of respiratory alkalosis include

A) light headedness.
B) agitation.
C) tingling sensations.
D) all of the above.

Question 29

Hyperventilation leads to

A) respiratory acidosis.
B) respiratory alkalosis.
C) metabolic acidosis.
D) metabolic alkalosis.

Question 30

Obstruction of the airways leads to

A) respiratory acidosis.
B) respiratory alkalosis.
C) metabolic acidosis.
D) metabolic alkalosis.

Question 31

Which of the following metabolic processes releases hydrogen ions to body fluids?

A) Anaerobic respiration of glucose
B) Aerobic respiration of glucose
C) Incomplete oxidation of fatty acids
D) All of the above

Question 32

The parts of an amino acid that are important in the protein buffer system are the

A) amino and R groups.
B) amino and carboxyl groups.
C) monocarbonate and bicarbonate groups.
D) monohydrogen phosphate and dihydrogen phosphate groups.

Question 33

Which of the following would be most helpful in treating hypocalcemia?

A) Removing the parathyroid glands
B) Administering high doses of vitamin D and calcium salts
C) Stimulating calcium excretion by the kidneys
D) Avoiding foods that are high in calcium

Question 34

Which of the following is a physiological buffer?

A) Bicarbonate buffer
B) Phosphate buffer
C) Protein buffer
D) Renal mechanism

Question 35

Acidosis is a pH of arterial blood

A) below 4.5
B) above 4.5
C) below 7.35
D) above 7.35

Question 36

Prolonged vomiting, in which only the stomach contents are lost, leads to

A) respiratory acidosis.
B) respiratory alkalosis.
C) metabolic acidosis.
D) metabolic alkalosis.

Question 37

Diabetes mellitus, in which fatty acids react to produce ketone bodies, leads to

A) respiratory acidosis.
B) respiratory alkalosis.
C) metabolic acidosis.
D) metabolic alkalosis.

Question 38

Acid-base buffer systems minimize pH changes by

A) converting weak acids to strong acids.
B) converting strong acids to weak acids.
C) increasing breathing rate.
D) promoting the excretion of hydrogen ions.

Question 39

Metabolic alkalosis may be caused by

A) prolonged vomiting.
B) taking too many antacids.
C) gastric lavage ("stomach pumping").
D) all of the above.

Question 40

The respiratory center is most likely to increase the breathing rate if the

A) concentration of carbonic acid is decreasing.
B) pH of body fluids is decreasing.
C) pH of body fluids is increasing.
D) concentration of sodium bicarbonate is increasing.

Question 41

Respiratory alkalosis can be

A) caused by anything that decreases breathing rate.
B) compensated for by a decreased secretion of bases in the kidneys.
C) compensated for by a decreased respiratory rate.
D) characterized by muscle paralysis.

Question 42

The buffer system in blood is formed by

A) the chloride shift through the cell membranes.
B) deoxyhemoglobin generated in white blood cells.
C) phosphate buffer in the renal system.
D) hemoglobin binding hydrogen ions in red blood cells.

Question 43

The sequence of symptoms of heatstroke is

A) neurological symptoms, dizziness, skin reddening, and then headache and racing heart.
B) headache, dizziness, exhaustion, then sweating, which stops as the skin becomes red, hot, and dry.
C) intense itching, profuse sweating, kidney failure, racing pulse, headache.
D) fever, itching, redness, headache, numb extremities, vomiting.

Question 44

Dehydration is caused by

A) excessive sweating.
B) prolonged water deprivation.
C) prolonged vomiting or prolonged diarrhea.
D) all of the above.

Question 45

People who are at high risk for heatstroke include

A) people prone to fevers and infants.
B) people who have mice for pets.
C) mountain climbers and elderly marathoners.
D) athletes who exercise in high heat, soldiers in the desert.

Question 46

Hyponatremia is

A) another term for dehydration.
B) caused by elevated levels of aldosterone.
C) high blood sodium.
D) more likely in runners who are in a long race, have an extreme body mass index, and drink a great deal during the event.

Question 47

Water intoxication causes

A) low blood sodium.
B) high blood sodium.
C) low blood potassium.
D) abnormal accumulation of extracellular fluid.

Question 48

Hypernatremia

A) can be caused by high fever.
B) can be caused by low levels of ADH.
C) causes confusion, stupor, and coma.
D) is all of the above.

Question 49

Metabolic acidosis can be

A) caused by a decreased breathing rate.
B) caused by a decreased gas exchange surface area.
C) compensated for by the retention of large numbers of H⁺ in the kidneys.
D) compensated for by an increased breathing rate and depth.

Question 50

The greatest output of electrolytes normally is in urine.

Question 51

Normally, fluid enters the lymphatic capillaries as a result of active transport.

Question 52

Addison disease is characterized by

A) aldosterone deficiency and loss of extracellular sodium.
B) aldosterone deficiency and gain of extracellular sodium.
C) aldosterone excess and loss of extracellular sodium.
D) aldosterone excess and gain of extracellular sodium.

Question 53

The technical term for water intoxication is

A) hypoglycemia.
B) hypocalcemia.
C) hyponatremia.
D) hypoxia.

Question 54

The thirst mechanism is usually not triggered until the volume of the body water has been decreased by 5-10%.

Question 55

Edema is

A) a response to dehydration.
B) caused by hyperproteinemia.
C) abnormal accumulation of extracellular fluid.
D) caused by depressed venous pressure.

Question 56

In a healthy body, the volume of water remains relatively stable at all times.

Question 57

Effects of hypokalemia include

A) muscle weakness.
B) acne.
C) sweating.
D) diabetes.

Question 58

The hormone ADH is released from the anterior lobe of the pituitary gland.

Question 59

Hyperkalemia can be caused by

A) renal disease, which reduces potassium excretion.
B) drugs that promote renal conservation of potassium.
C) insufficient secretion of aldosterone.
D) all of the above.

Question 60

Factors that alter water balance will also alter electrolyte balance.

Question 61

Arterial blood with a pH below 7.35 produces _____________.

Question 62

Parathyroid hormone increases phosphate reabsorption from the renal tubules.

Question 63

The kidneys help to regulate the hydrogen ion concentration of body fluids by altering the rate at which hydrogen ions are secreted.

Question 64

Water obtained as a by-product of the oxidation of various nutrients is called water of _____.

Question 65

The intracellular fluid compartment includes all water and electrolytes enclosed by a _____ _____.

Question 66

Chemical buffer systems act rapidly against shifts in pH, whereas physiological buffer systems function more slowly.

Question 67

Carbon dioxide reacts with water to form _____ _____.

Question 68

The volume of urine produced is regulated mainly by the activity in the distal convoluted tubule and the _____ duct.

Question 69

Arterial blood with a pH above 7.45 produces _____________.

Question 70

A blood pH of 7.2 inhibits the respiratory center in the brainstem and decreases CO₂ level.

Question 71

Sometimes the carboxyl groups of proteins release hydrogen ions.

Question 72

The part of the brain that helps regulate hydrogen ion concentrations is the _______ center.

Question 73

Kidneys help to regulate acid-base balance of the blood by secreting OH^-.

Question 74

The concentration of calcium ions in extracellular fluid is regulated primarily by a hormone secreted by the _____ glands.

Question 75

A protein functions as an acid-base buffer system by the -COOH group of a molecule accepting H⁺ in the presence of excess acid and the NH₃ group of a molecule releasing H⁺ in the presence of excess base.