L2: Body Fluid Compartments & Water Transport Flashcards
Total Body Water (TBW) of Men
60% of body weight
Total Body Water (TBW) of Women
50% of body weight
ICF
60% of TBW
ECF
40% of TBW
What does the ECF consist of?
- Interstitial fluid
- Plasma
- Transcellular flluid
Interstitial fluid is ___% of ___ fluid
75% of ECF
Plasma volume is ___% of ___ fluid
20% of ECF
Transcellular fluid is ___% of ____ fluid
5% of ECF
Blood volume =
PV/(1 - Hct)
Composition of Interstitial fluid (avg 13L)
Bulk IF (8L)
Bone (2L)
Dense connective tissue (3L)
Avg osmolality of all body fluids
290 mOsm
Men Hct
45%
Women Hct
40%
Average Blood Volume for 70kg male
BV = PV/(1 - Hct) PV = 70*0.6*0.4*0.2 = 3L BV = 3/(1 - 0.45) = 5.45L
ICF [Na+]
15mM
ICF [K+]
120mM
ICF [Cl-]
20mM
ICF [Protein]
4mM
IF [Na+]
145mM
IF [K+]
4.5mM
IF [Cl-]
116mM
IF [Protein]
0mM
Blood plasma ion concs
Similar to IF
Major difference between plasma and IF
absence of plasma proteins from interstitium
Gain =
Correction / Error
If a diatomic molecule dissociates then how many osmols are produced from 1 mole of the molecule?
2 osmols
Isosmotic solution causes
no change in cell volume
hypotonic solution causes
cell swelling
hypertonic solution causes
cell shrinkage
how much energy goes into maintaining resting ion gradients?
30%
