Body Fluids

Question 1

60% of body weight

Answer 1

Total Body Water (TBW)

Question 2

Marker for TBW

Answer 2

Tritiated water

Question 3

Marker for ECF
Large molecule that CANNOT cross cell membranes
Excluded from the ICF

Answer 3

Mannitol

Question 4

Marker for PLASMA VOLUME
Binds to serum albumin
Confined to the plasma compartment

Answer 4

Evans blue

Question 5

Dilution Method Formula

Answer 5

VOLUME = amount injected - amount excreted/ concentration

Question 6

A 70 kg man is administered inulin. Because it is freely filtered and not secreted or reabsorbed, inulin offers an accurate calculation of GFR. Inulin would be found in what amount of this patient’s body water?

Answer 6

In order to answer this question, you need to know two pieces of information about body fluid compartments

. First of all, you need to remember
the 60-40-20 rule related to body weight. 60% of body weight is total body water, 40% of body weight is intracellular fluid and 20% is extracellular fluid

Inulin is found in the extracellular fluid and can be used to measure extracellular fluid volume
. To answer this question, it easiest to divide 70 by 10, which tells us that 10% of her body weight is 7 kg.

Multiplying this value by 2 would give us 20% of body weight, or 14 kg, which is equivalent to 14 L of water

14 L

Question 7

The major cation of the extracellular fluid is .

Answer 7

Na

Question 8

Women typically have a (higher/lower) percentage of body water.

Answer 8

LOWER

Question 9

Approximately two-thirds of body water by volume is contained in the (intracellular/extracellular) fluid compartment.

Answer 9

ICF

Question 10

The fluid compartment of the body is divided into plasma and interstitial fluid.

Answer 10

ECF

Question 11

The major anions of the extracellular fluid are (two) .

Answer 11

Cl

Bicarbonate

Question 12

The major cations in the intracellular fluid are (two) .

Answer 12

K

Mg

Question 13

Approximately 40% of body weight is in the (intracellular/extracellular) fluid compartment.

Answer 13

ICF

Question 14

Approximately one-third of body water by volume is contained in the (intracellular/extracellular) fluid compartment.

Answer 14

ECF

Question 15

fluid is the fluid in microscopic spaces between cells.

Answer 15

Interstitial fluid

Question 16

Exchange of fluid from plasma to the interstitial fluid occurs across walls.

Answer 16

Capillary walls

Question 17

The major anions of the intracellular fluid are proteins and like ATP and ADP.

Answer 17

Organic phosphates

Question 18

Isotopic water, like D2O or tritiated water, are used as a markers for (intracellular/extracellular/total) body water.

Answer 18

TBW

Question 19

Generally speaking, obese individuals will have a (higher/lower) percentage of body weight as water.

Answer 19

LOWER

Question 20

A large molecular weight protein or sugar like mannitol or inulin would be distributed only to the (intracellular/extracellular) compartments.

Answer 20

ECF

Question 21

Of the one-third of body water in the extracellular fluid compartment, approximately 20% is found in the .

Answer 21

Plasma

Question 22

Hyperosmotic volume expansion, e.g. excess intake of sodium chloride, results in relatively greater increased volume in the (intracellular/extracellular) fluid compartment.

Answer 22

ECF

Question 23

Hypo-osmotic volume expansion, e.g. syndrome of inappropriate antidiuretic hormone, results in increased volume of the (intracellular/ extracellular/ both) fluid compartment(s).

Answer 23

ICF and ECF

Question 24

Infusion of isotonic saline results in a relatively greater volume increase of the (intracellular/extracellular) fluid compartment.

Answer 24

ECF

Question 25

NaCl, NaHCO3, and mannitol are generally assumed to be confined in the (intracellular/extracellular) fluid compartment(s).

Answer 25

ECF

Question 26

Hypo-osmotic volume contraction, like
adrenal insufficiency, can cause a relatively greater increased volume in the (intracellular/extracellular) intracellular fluid compartment(s).

Answer 26

ICF

Question 27

The of a body fluid compartment depends on the amount of solute contained.

Answer 27

VOLUME

Question 28

Hyperosmotic volume expansion, e.g. excess intake of hypertonic saline, results in a relatively greater volume DECREASE in the (intracellular/extracellular) fluid compartment.

Answer 28

ICF

Question 29

Sweat is (isosmotic/hyposmotic/hyperosmotic) relative to extracellular fluid.

Answer 29

HYPOOSMOTIC

Question 30

Hyperosmotic volume contraction, like sweating, fever, or diabetes insipidus, can DECREASE the volume in the (intracellular/ extracellular/ both) fluid compartment(s).

Answer 30

BOTH

Question 31

Iso-osmotic volume contraction like diarrhea and burns can cause a relatively greater volume DECREASE in the (intracellular/extracellular) fluid compartment(s).

Answer 31

ECF

Question 32

The normal osmolarity of body fluids is milliosmoles/liter

Answer 32

290

Question 33

Volume contraction describes a decrease in (intracellular/extracellular) fluid volume.

Answer 33

ECF

Question 34

Intracellular osmolarity is (greater than, less than, equal to) extracellular osmolarity in the steady state.

Answer 34

EQUAL

Question 35

The terms hyperosmotic, hypoosmotic, and isosmotic refer to the osmolarity of the (intracellular/extracellular) fluid.

Answer 35

ECF