Body Fluids
In human body 60 % of the total body weight is comprised of fluids.
Only 40 % of the total body weight is found jn the form of solids like mucle mass
, bone , fat etc.
Now let's talk about the fluids portion. 2/3 portion of this
fluid is preant inside the cells, which is known as Intracellular Fluid (ICF).
1/3 portion of this fluid in the body is found outside the cells
, which is known as Extra Cellular Fluid (ECF). Now This Extracellular fluid is
divide into 3 categories viz
1. Interstitial fluid – Whatever fluid that ia found in between the cells is known as Interstitial Fluid. This interstital fluid is found outside the cells and Outside the Blood Vessels.
2. Blood – Blood flows In the blood vessels.This Blood consists of plasma and some solutes like proteins, electrolytes, blood cells etc.
3.Transcellular Fluid – Fluid in this category are
different than above 2 categories. For e.g. CSF, Lymph, Synovial fluid in Synovial
Joints etc.
Now we will talk about the various fluid transport mechanisms.
But before we jump to thia topic we need to underatand 2 Terms
A.Solute – Anything which dissolves itself is known
as solute. For e.g. if we take a spoonful sugar and pour this in a container filled
with water this sugar will start to dissolve in this water , in this situation the
Sugar will be known as Solute.
B.Solvent – Solvent is something which has the capacity
to dissolve the solute. Like we have discussed in the above example Sugar gets dissolved
in the water so here water works as Solvent which causes the sugar to dissolve in
it.
So , Now I think we can proceed to
our topic Which Is Body Fluids Transport. So movemnt of body fluid in our body is
carried out through following mechanisms
1.Diffusion – It means dissolving of solute in solution.
It means diffusion is known as transfer of solute from its higher concentration
to its lower concentration which leads to balancing the concentration of the solution
throughout it. Now it may happen across a permeable/Semipermeable Membrane.
You might be thinking that what is a semi permeable
membrane. Well it simply means the menbrane which allowes or permits only selected
solute and solution to cross it. So it selectively
allows to pass solute and solution through it, It is also known as Selectively Permeable
Membrane.
2. Osmosis- It means transfer of solvents from lower concentration of solute to higher concentration of fluid via a semipermeable membrane. Now here the important thing that we have to keep in mind is semi permeable membrane. Solute binds solvents. For an example Na+ has the capacity to bind water, so here Na+ is solute and water is the solvent. Wherever the concentration of Na+ will be more, water will move towards it. I think Now it is clear to You All Guys.
Here are some terms that you need to understand before we proceed further with this chapter
1. Hypotonic Solution - If we break down the word Hypotonic, It is made up of two words Hypo + Tonicity. Hypo means Less and Tonicity means Concentration The osmolality of plasma is around 273 - 295 mmol/L . So any solution which falls below this osmolality range will be known as hypotonic solution. For an e.g. - 0.45% NS is a hypotonic Solution.
2.Hypertonic Solution - Hyper means More.The osmolality of plasma is around 273 - 295 mmol/L . So any solution which falls above this osmolality range will be known as hypertonic solution. For an e.g. - 3% NS is a hypertonic Solution.
3.Isotonic Solution - Iso means Same.The osmolality of plasma is around 273 - 295 mmol/L . So any solution which falls in between this osmolality range will be known as Isotonic solution. For an e.g. - 0.9% NS is a Isotonic Solution.