Body Fluids
The
total body water in adults of average build is about 60% of body weight. This
proportion is higher in babies and in young adults. It is lower in old and
obese people of all ages. About 22 % of body weight is extracellular, water and
about 38% is intracellular water.
Extracellular:
22% consists of blood, plasma,
lymph, csf, and fluid in interstitial spaces of body. It is also present in
synovial fluid, pericardial fluid, pleural fluid.
Intracellular:
38% the composition of intracellular
fluid is largely controlled by cell
itself, because there are selective uptake and discharge mechanisms present in
the cell membrane.
Example: Na (Sodium)
levels are more in ECF than in ICF. This concentration is essential for
function of excitable cells (Nerve & Muscle). Substance found in ICF are
ATP, protein and potassium in higher concentrations.
