Electrolytes

Question 1

major cations in the body

Answer 1

sodium, potassium, calcium, magnesium

Question 2

major anions in the body

Answer 2

chloride, bicarbonate, phosphate, sulfate, organic acids, protein

Question 3

average water content of the human body

Answer 3

40% to 75% of total body weight

Question 4

fluid inside the cells; accounts for about two-thirds of total body water

Answer 4

Intracellular fluid (ICF)

Question 5

accounts for one-third of total body water

Answer 5

Extracellular fluid (ECF)

Question 6

Extracellular fluid (ECF) is subdivided into:

Answer 6

Intravascular fluid
Interstitial fluid
Transcellular fluid

Question 7

Normal plasma is about –% water, with the remaining volume occupied by lipids and proteins.

Answer 7

93%

Question 8

The water content of plasma is how many percent higher than that of whole blood?

Answer 8

12%

Question 9

Sweat contains about —mmol/L of sodium and — mmol/L of potassium.

Answer 9

Sweat contains about 50 mmol/L of sodium and 5 mmol/L of potassium.

Question 10

is the main determinant of the extracellular volume.

Answer 10

Salt content

Question 11

a mechanism that requires energy to move ions across cellular membranes.

Answer 11

Active transport

Question 12

the passive movement of ions (no energy consumed) across a membrane

Answer 12

diffusion

Question 13

refer to the properties of a solution that are influenced by the number of molecules in solution, but not their individual composition

Answer 13

colligative properties

Question 14

four types of colligative properties

Answer 14

Boiling point
Freezing point
Osmotic pressure
Vapor pressure

Question 15

is a physical property of a solution that is based on the concentration of solutes per kilogram of solvent.

Answer 15

osmolality

Question 16

osmolality is regulated by — through the sensation of thirst

Answer 16

hypothalamus

Question 17

When the osmolality of the blood is increased, two processes occur

Answer 17

sensation of thirst
arginine vasopressin hormone (formerly antidiuretic hormone)

Question 18

Acts on the collecting ducts of kidneys to increase water reabsorption, controlling water excess

Answer 18

Arginine vasopressin hormone

Question 19

Arginine vasopressin hormone is secreted by

Answer 19

posterior pituitary gland

Question 20

method used to measure all particles (molecules and ions) in solution; measure of osmolality

Answer 20

osmometry

Question 21

represents the difference between the measured and calculated osmolality.

Answer 21

osmomal gap

Question 22

the osmomal gap should be

Answer 22

< 15

Question 23

Measuring serum and urine osmolality is useful in assessing what?

Answer 23

electrolyte disorders and acid-base status

Question 24

Major molecules measured by serum osmolality include

Answer 24

sodium, chloride, glucose, and urea

Question 25

Particles in solution cause the freezing point of pure water to be ---

Answer 25

decreased

Question 26

what is the relationship between the osmolality of the solution (amount of particles present) and the vapor pressure

Answer 26

inverse relationship

Question 27

increased thirst; caused by excess intake of water.

Answer 27

polydipsia

Question 28

a disease of water and salt imbalance; deficiency of AVP, causing increased urinary excretion, which may or may not interfere with Na+ concentration.

Answer 28

diabetes insipidus

Question 29

Renin-Angiotensin-Aldosterone System (RAAS) responds primarily to...

Answer 29

decreased blood volume

Question 30

Renin-Angiotensin-Aldosterone System (RAAS) responds to low blood pressure by

Answer 30

- secreting renin - renin converts the hormone angiotensinogen to angiotensin I, which then becomes angiotensin II - Angiotensin II causes both vasoconstriction, which quickly increases blood pressure, and secretion of aldosterone (increases reabsorption of Na+)

Question 31

osmolality serum normal value

Answer 31

257 - 295 mOsm/kg

Question 32

sodium is also known as

Answer 32

natrium

Question 33

It is the major extracellular cation

Answer 33

sodium

Question 34

It is the principal osmotic particle outside the cell.

Answer 34

sodium

Question 35

percent of filtered sodium reabsorbed in proximal tubule

Answer 35

60 - 70%

Question 36

Blood volume is regulated by changes in --- balance

Answer 36

sodium

Question 37

reference range for sodium serum/plasma

Answer 37

135 - 145 mmol/L

Question 38

Hormones Affecting Plasma Sodium Levels

Answer 38

aldosterone, atrial natriuretic factor, urodilantin, angiotensin II and catecholamines

Question 39

this hormone promotes sodium retention and potassium excretion.

Answer 39

aldosterone

Question 40

Blocks aldosterone and renin secretion and inhibits the action of angiotensin II and vasopressin

Answer 40

atrial natriuretic factor

Question 41

Causes natriuresis (increased renal sodium excretion)

Answer 41

atrial natriuretic factor

Question 42

Hypernatremia is characterized by increased plasma sodium of what value

Answer 42

> 145 mmol/L

Question 43

is the major defense against hyperosmolality and hypernatremia

Answer 43

thirst

Question 44

Hyponatremia is usually associated with what?

Answer 44

hypovolemia

Question 45

Serum Na+ indicative of severe deficit of water

Answer 45

> 165 mmol/L

Question 46

Serum Na+ indicative of moderate deficit of water

Answer 46

150 - 160 mmol/L

Question 47

It is the most common electrolyte disorder encountered in clinical practice.

Answer 47

Hyponatremia

Question 48

Hyponatremia is defined as having plasma sodium of what value

Answer 48

< 135 mmol/L

Question 49

is the most common cause of hyponatremia either due to sodium loss or water retention.

Answer 49

Decreased osmolality

Question 50

For every 100 mg/dL increase in blood glucose, serum sodium decreases by

Answer 50

1.6 mmol/L

Question 51

It is characterized by continuous secretion of ADH in the absence of stimulus.

Answer 51

Syndrome of inappropriate ADH Secretion (SIADH)

Question 52

It is the reduction of serum sodium concentration caused by a systemic error in measurement

Answer 52

Pseudohyponatremia

Question 53

the most common case of pseudohyponatremia is

Answer 53

in-vitro hemolysis

Question 54

Emission Flame Photometry of sodium

Answer 54

yellow

Question 55

cushing's syndrome is caused by

Answer 55

increased intake or retention of sodium