Electrolytes

Question 1

What is the major intracellular cation?
a. Potassium
b. Calcium
c. Magnesium
d. Sodium

Answer 1

a. Potassium

Question 2

. What is the major extracellular cation?
a. Sodium
b. Chloride
c. Magnesium
d. Calcium

Answer 2

a. Sodium

Question 3

Osmolality can be defined as a measure of the concentration of a solution
based on the
a. Number of dissolved particles
b. Number of ionic particles present
c. Number and size of the dissolved particles
d. Density of the dissolved particles

Answer 3

a. Number of dissolved particles

Question 4

. Hyponatremia may be caused by each of the following EXCEPT
a. Hypomagnesemia
b. Aldosterone deficiency
c. Prolonged vomiting or diarrhea
d. Acute or chronic renal failure

Answer 4

a. Hypomagnesemia

Question 5

Hypokalemia may be caused by each of the following EXCEPT
a. Acidosis
b. Prolonged vomiting or diarrhea
c. Hypomagnesemia
d. Hyperaldosteronism

Answer 5

a. Acidosis

Question 6

6. Hyperkalemia may be caused by each of the following EXCEPT
   a. Alkalosis
   b. Acute or chronic renal failure
   c. Hypoaldosteronism
   d. Sample hemolysis

Answer 6

a. Alkalosis

Question 7

The main difference between a direct and indirect ISE is
a. Sample is diluted in the indirect method, not in the direct method
b. The type of membrane that is used
c. Direct ISEs use a reference electrode, whereas indirect ISEs do not
d. Whole blood samples can be measured with the direct method and not
with the indirect method

Answer 7

a. Sample is diluted in the indirect method, not in the direct method

Question 8

8. Which method of analysis will provide the most accurate electrolyte results if
   a grossly lipemic sample is used?
   a. Direct ISE
   b. Indirect ISE
   c. Flame emission photometry
   d. Atomic absorption

Answer 8

a. Direct ISE

Question 9

The most frequent cause of hypermagnesemia is due to
a. Renal failure
b. Increased intake of magnesium
c. Hypoaldosteronism
d. Acidosis

Answer 9

a. Renal failure

Question 10

A hemolyzed sample will cause falsely increased levels of each of the
following EXCEPT
a. Sodium
b. Potassium
c. Phosphate
d. Magnesium

Answer 10

a. Sodium

Question 11

The largest portion of total body water is found in which tissue?
a. Intracellular fluid
b. Extracellular fluid
c. Intravascular extracellular fluid
d. Interstitial cell fluid
e. Plasma

Answer 11

a. Intracellular fluid

Question 12

Osmoreceptors in the hypothalamus are key to regulating blood osmolality.
Typically, a 1% to 2% shift in osmolality causes a _______ change in
circulating concentration of AVP.
a. Twofold
b. Fourfold
c. Eightfold
d. Tenfold

Answer 12

b. Fourfold

Question 13

The quantitative relationship between changes in blood osmolality and the
normal expected response by AVP is best described as a(n):
a. Indirect relationship
b. Direct relationship
c. Logarithmic relationship
d. There is no quantitative relationship

Answer 13

c. Logarithmic relationship

Question 14

The sample of choice for measuring blood osmolality is:
a. Serum
b. Plasma
c. Whole blood
d. Serum or plasma may both be used

Answer 14

a. Serum

Question 15

With increased water loss, burn patients are most likely to also experience:
a. Hypernatremia
b. Hyponatremia
c. Hypomagnesemia
d. Hypoosmolality

Answer 15

a. Hypernatremia

Question 16

. Which plasma electrolyte has the most narrow reference range and is MOST
strictly regulated by the body?
a. Sodium
b. Magnesium
c. Calcium
d. Chloride
e. Potassium

Answer 16

e. Potassium

Question 17

True or False? RBCs are key for oxygen transport, carbon dioxide transport,
and maintaining electroneutrality in the blood.

Answer 17

TRUE