body fluids Flashcards
total body fluid
42 L
extracellular fluid - plamsa
3L
extracellular fluid - interstitial fluid
10L
extracellular fluid - transcellular fluid
1L
intracellular fluid
28 L
rough water intake daily
2 L
daily urine production
800 - 2000 ml/day
volume of other water loss
skin = 300-400ml
respiratory tract = 300-400 ml
ext Na+
140 mM
135-145
ext K+
4 mM
3.5-5
ext Ca2+
- 4 mM
2. 12 - 2.62
ext Cl-
100 mM
95-105
ext HCO3-
25 mM
22-29
ext H+
40 nM
pH = 7.4
int Na+
5-15 mM
int K+
140 mM
int Ca 2+
0.1 micromolar (um)
int Cl-
less than extracellular but big range
int HCO3-
10-20 mM
int H+
50-100 nM
daily sodium intake
max recommended = 2.4g
daily intake
less than 3.6 g /day
estimated daily sodium loss
23 mg
plasma osmolarity
290 mOsM
urine osmolarity
30-1200 mOsM
pH calc
-log10[H+]
normal pH values
[H+] = 40nM pH = 7.4
defence against alkalosis and acidosis
buffers
ventilatory mechanisms
renal mechanisms
use of Henderson hasselbalch equation
estimate the pH of a buffer solution
Henderson Hasselbalch equation
pH = Pka + log10 [A-]/[HA]
A- = conjugate base HA = weak acid
main intracell buffer
haemoglobin
can also have some proteins and phosphate
main extracell buffer
carbonic anhydrase/ bicarbonate
albumin
ammonia
buffer concept
can resist changes in ph when small amounts of acid or base are added
