Unit 1: Osmolarity and Tonicity

Question 1

Concentration =

Answer 1

Concentration = solute #/volume

Question 2

Osmosis - water moves from ____ solute to ____ solute concentration (or water helps equilibrate solute concentrations when they are ______)

Diffusion - solute moves from _____ concentration to _____ concentration

Answer 2

low, high
non-penetrating

high, low

Question 3

Urea –>
Ions (Na+, K+, etc) –>
Glucose –>

Answer 3

Urea –> freely penetrating
Ions (Na+, K+, etc) –> non-penetrating
Glucose –> partially penetrating

Question 4

Molarity =

Answer 4

moles/L

Question 5

Osmolarity =

Answer 5

osmoles/L

Question 6

Osmoles take into consideration the _____ of the solute in solution.

Answer 6

dissolution

Question 7

1 mole of NaCl turns into…

Answer 7

1 mole of Na+
and 1 mole of Cl-
2 osmoles of NaCl

Question 8

1 mole of glucose turns into…

Answer 8

1 mole of glucose
1 osmole of glucose

Question 9

The osmolarity of 0.150M NaCl is approximately:

Answer 9

0.3 OsM

Question 10

The osmolarity of 0.50M glucose is approximately:

Answer 10

0.5 OsM

Question 11

Osmolarity compares any ______ (even a cell).

Describes a _______ compared to another.

Mechanism of equilibrium:

Answer 11

two solutions

solution’s concentration

Diffusion

Question 12

Tonicity describes a ______ compared to a _____

Mechanism of equilibrium:

Only _____ solute

Answer 12

solution, cell

osmosis

non-penetrating

Question 13

Tonicity:
Hypertonic: water moves ______ the cell
Isotonic: no ____ movement of water
Hypotonic: water moves _____ the cell

Answer 13

out of

net

into

Question 14

60% of ______ = TBW (total body water)

Answer 14

body weight (kg)

Question 15

Markers – indicate volumes of body compartments

Deuterium oxide (D2O) –>
Inulin –>
Evan’s blue –>

Answer 15

Deuterium oxide (D2O) –> total body water
Inulin –> ECF
Evan’s blue –> plasma

Question 16

Plasma is around 25% of _____

Answer 16

ECF

Question 17

D2O marks _______

Answer 17

TBW

Question 18

ECF is _____ of TBW
ICF is ______ of TBW

Answer 18

33%
67%

Question 19

Glucose is partially penetrating, meaning it can move across the membrane into the cell, but then it ______ the cell.

Therefore, only adds to ____ volume

Answer 19

stays in the cell

ICF

Question 20

Urea is freely penetrating. NO VOLUME _______ for a freely penetrating solute

Answer 20

moves or changes

Question 21

Dehydration:

Sweating = Losing _____ fluid from ____
Lose more _____ than _____

Plasma osmolarity ____

Lose ____ volume

Answer 21

hypoosmotic
ECF

water, solute

increases

ECF + ICF
*Lose water from ICF

Question 22

Hemorrhage:

Bleeding = Losing _____ fluid from ___

Plasma concentration ____

Lose ____ volume

Answer 22

isoosmotic
ECF

does not change

only ECF

Question 23

In dehydration, all solute lost comes from the _____.

Answer 23

ECF

Question 24

When treating dehydration, you need to:

1) Regain ____ loss
2) ____ cells
3) _____ osmolarity

Answer 24

1) Regain volume loss
2) Rehydrate cells
3) Lower osmolarity

Question 25

The appropriate solution to administer to the dehydrated soldier will be:

Answer 25

Hypoosmotic (lowering osmolarity) Hypotonic (solution less than cell, water moves into cell --> hydrating cell)

Question 26

When treating hemorrhage, you need to think about: 1)

Answer 26

1) Regain volume loss isotonic

Question 27

RBC Cell Responses: initial --> ultimate -->

Answer 27

initial --> osmolarity ultimate --> tonicity

Question 28

Cell will only burst/hemolyze if there are...

Answer 28

NO NON-PENETRATING solutes outside

Question 29

If you were to administer a solution that replaced exactly what the soldier lost, the osmolarity of that solution would be: _______ mOsM explain the math

Answer 29

subtract start chart total solute - final total solute = how much solute lost (0.648 osmoles) Divide this by how many L lost started off 70 kg, went to 64 kg 70 L - 64 L = 6 L 0.648 osmoles/6 L

Question 30

Place an RBC (300 mOsM) in 200 mOsM NaCl and 400 mOsM urea: Total concentration of the solution is _____ mOsM cell will _____ then _____

Answer 30

600 mOsM shrink, swell

Question 31

Draw a time line of the volume change of the cell when placed in 300 mOsM NaCl and 300 mOsM urea: Initial response due to: _____ Ultimate response due to: ____

Answer 31

Line would dip down and then return to the same level hyperosmotic isotonic (back to its original shape)

Question 32

Normal saline (NaCl): Also known as _____ Concentration: Osmolarity: Tonicity:

Answer 32

Also known as 0.9% saline Concentration: 300 mOsM Osmolarity: Isoosmotic Tonicity: Isotonic

Question 33

D5-Normal saline: Also known as _____ Concentration: Osmolarity: Tonicity:

Answer 33

Also known as 5% dextrose in water Concentration: 578 mOsM Osmolarity: hyperosmotic Tonicity: isotonic

Question 34

D5W Also known as _____ Concentration: Osmolarity: Tonicity:

Answer 34

Also known as 5% dextrose in water Concentration: ~278 mOsM Osmolarity: isosmotic Tonicity: hypotonic

Question 35

Half-normal saline Also known as _____ Concentration: Osmolarity: Tonicity:

Answer 35

Also known as 0.45% saline Concentration: 150 mOsM Osmolarity: hyposmotic Tonicity: hypotonic

Question 36

D5-half-normal saline Also known as _____ Concentration: Osmolarity: Tonicity:

Answer 36

Also known as 5% dextrose in 0.45% saline Concentration: 428 mOsM Osmolarity: hyperosmotic Tonicity: hypotonic

Question 37

An intern gives free water (just water) into the IV of a patient to correct hypernatremia (high sodium plasma []) of a patient. The patient died. What was a possible cause of this patient's death?

Answer 37

red blood cells hemolysis (No NP solutes)

Question 38

The appropriate IV solution(s) to correct hemorrhage is/are...

Answer 38

Normal saline and D5-normal

Question 39

Standard IV Solutions Isotonic: Hypotonic:

Answer 39

Normal saline D5-normal saline D5W 1/2-normal saline D5-1/2-normal

Question 40

Administer D5-1/2 normal saline to subject (osmolarity = 300 mOsM). What are potential side effects of this IV solution?

Answer 40

Cellular edema (fluid buildup within cells)

Question 41

Osmolarity: Based on ______ of molecules Tonicity: Takes _____ of particles into account ______ ONLY Always describes _____ compared to ___

Answer 41

total number Non-penetrating SOLUTION, cell

Question 42

Penetrating solutes: Freely Penetrating: - Can cross cell membrane _____ transporter - Not _____ by cell - Ex. _____ Partially Penetrating: - Can cross cell membrane _____ transporter - ____ by cell so can't move back across (adds to _____) - Ex. _____

Answer 42

without metabolized urea with Metabolized (adds to ICF) glucose, sugars, fructose

Question 43

Non-Penetrating solutes Completely non-penetrating: - Can't cross cell membrane unless ______ - Ex. ____ Functionally non-penetrating: - Can cross cell membrane but no ____ - Ex. _____

Answer 43

exocytosed proteins net movement NaCl