02a: Fluids and Transport Flashcards Preview

CFoM > 02a: Fluids and Transport > Flashcards

Flashcards in 02a: Fluids and Transport Deck (57)
Loading flashcards...
1
Q

TBW stands for (X) and is (Y)% BW.

A
X = Total body water
Y = 60
2
Q

TBW can be divided into (X) and (Y).

A
X = ECF
Y = ICF
3
Q

ECF is (X)% of (Y) and (Z)% of BW.

A
X = 33
Y = TBW
Z = 20
4
Q

ICF is (X)% of (Y) and (Z)% of BW.

A
X = 67
Y = TBW
Z = 40
5
Q

Fluid in circulatory system is called (X). Amount of fluid is (Y)% of (Z).

A
X = plasma
Y = 20
Z = ECF
6
Q

Interstitial fluid is (X)% of (Y).

A
X = 80
Y = ECF
7
Q

Osmolality of intracellular water is about (X). And of extracellular water is about (Y).

A

X = Y = 300 mOsmol/L H20

Same in all compartments!

8
Q

Osmolality is a measure of:

A

Solute (salt/ion) per kg solvent

9
Q

Normal Na concentration in ECF and ICF.

A

ECF: 140 mEq/L H20
ICF: 12 mEq/L H20

10
Q

Normal K concentration in ECF and ICF.

A

ECF: 4 mEq/L H20
ICF: 150 mEq/L H20

11
Q

Normal Ca concentration in ECF and ICF.

A

ECF: 2 mEq/L H20
ICF: .00010 mEq/L H20

12
Q

Normal HCO3 concentration in ECF and ICF.

A

ECF: 24 mEq/L H20
ICF: 10 mEq/L H20

13
Q

Normal protein concentration in ECF and ICF.

A

ECF: 16 mEq/L H20
ICF: 60 mEq/L H20

14
Q

In which specific compartments in ECF can proteins be found?

A

Plasma; very very little in interstitial fluid

15
Q

The (X) and (Y) of ECF are separated by (Z) membrane. Speak to its permeability.

A
X = plasma
Y = interstitia
Z = endothelium

Very permeable

16
Q

ECF and ICF separated by (X). Speak to its permeability.

A

X = plasma membrane

Selective permability

17
Q

Macroscopic electroneutrality states:

A

In each compartment, positive charges equal the negative charges on a macroscopic level

18
Q

Permeability equation

A

P = (D)(beta)/(deltaX)

19
Q

Which characteristic(s) of solute affect permeability?

A
  1. Size (smaller MW, larger diffusion coefficient)

2. Its solubility in lipids (more soluble, larger partition coefficient)

20
Q

How is the partition coefficient calculated?

A

Concentration of solute in lipid/Concentration of solute in water

21
Q

Net flux equation.

A

J = P(C1-C2)

22
Q

Net flux equation.

A

J = P(C1-C2)

23
Q

Which type of molecules can pass through PM via simple diffusion?

A
  1. Hydrophobic molecules

2. Small, uncharged, polar molecules

24
Q

List some ions that can pass PM via simple diffusion.

A

None!

25
Q

List some small, polar molecules that can pass PM via simple diffusion.

A

Water, urea, glycerol, CO2

26
Q

O2 (can/can’t) pass PM via simple diffusion, because it is what type of molecule?

A

Can; hydrophobic

27
Q

N2 (can/can’t) pass PM via simple diffusion, because it is what type of molecule?

A

Can; hydrophobic

28
Q

Benzene (can/can’t) pass PM via simple diffusion, because it is what type of molecule?

A

Can; hydrophobic

29
Q

The electrochemical potential takes into account:

A
  1. Concentration differences

2. Membrane potential

30
Q

What’s the typical membrane potential of a cell?

A

-60 mV (more negative inside)

31
Q

Under what conditions is an ion said to be in electrochemical equilibrium?

A

When the chemical and electrical gradients are equal in magnitude

32
Q

Define the equilibrium potential.

A

The membrane potential that is established at equilibrium for an ion under the existing concentration gradient.

33
Q

The Nernst equation exists to allow for the calculation of:

A

the equilibrium potential (Ei)

34
Q

The net driving force equation (taking into account equilibrium potential):

A

Vm - Ei

35
Q

What are the requirements to establish Gibbs-Donan Equilibrium?

A
  1. Macroscopic electroneutrality
  2. Concentration of permeant cations must be greater (and permeant anions less) on side with protein (electrical potential negative on side with protein)
  3. Osmolality greater on side with protein
36
Q

Is flux affected by transport proteins? How/why or why not?

A

Yes; permeability factor in determining flux is altered by proteins

37
Q

Which key things differ between channels and carriers?

A
  1. Translocation rate

2. Accessibility of binding sites

38
Q

(Carriers/channels) have selectivity filter. Provide example.

A

Channels; carboxyl ions in K channel act as selectivity filter

39
Q

List different types of gating in channel proteins.

A
  1. Voltage-gated
  2. Ligand-gated
  3. Stretch-activated
  4. Leak (spontaneous)
40
Q

Channels are accessible form (intra/extra)-cellular side.

A

Both

41
Q

T/F: One difference between channels and carriers is that, unlike carriers, net flux is always downhill in channels.

A

False - facilitated diffusion by carrier proteins is also always downhill flux

42
Q

(Intra/extra)-cellular side of carrier protein has greater affinity for substrate.

A

Both sides have same affinity!

43
Q

P-Type ATPases rely on (primary/secondary) active transport. Give examples.

A

Primary (phosphorylation);

  1. Ca-ATPase
  2. Na/K Pump
  3. H-ATPase
44
Q

Ca-ATPase is responsible for:

A

High extracellular Ca concentrations

45
Q

Describe movement of ions by Na/K pump.

A

2 K ions pumped into cell; 3 Na ions pumped out

46
Q

H-ATPase responsible for:

A

pH maintenance

47
Q

ABC transporters rely on (X) to function. Give examples of these transporters.

A

X = ATP

  1. MDR1
  2. CFTR
48
Q

What’s MDR1?

A

Multi-drug resistant ABC Transporter; pumps drugs out of cell

49
Q

What’s CFTR?

A

CF transmembrane regulatory; a Cl channel that opens upon binding ATP

50
Q

Give example of secondary active transport.

A

Na/glucose cotransport

51
Q

In the Na/glucose cotransport model, Na moves (uphill/downhill).

A

Downhill

52
Q

Define osmotic pressure.

A

Pressure required to prevent fluid movement into compartment, if concentration gradient exists.

53
Q

Osmotic pressure equation.

A

P = (sigma)RT(Cs)

54
Q

In osmotic pressure equation, what does sigma represent?

A

Reflection coefficient (how permeable is the solute)

55
Q

A solute as permeable as water will have a reflection coefficient value of:

A

0

56
Q

A completely impermeable solute will have reflection coefficient value of:

A

1

57
Q

What is responsible for oncotic pressure

A

The proteins present in plasma (and not in interstitia)