What is Osmosis?

What is Osmosis?

Osmosis is a movement of water a special kind of mixture of solutes like salt particles within the solvent like water particle.

In other words, during Osmosis water moves from an area of higher concentration to an area of lower concentration of water through a selectively permeable membrane that is a cell membrane. These cell membrane has small openings that let the water molecules pass through it but won’t allow the larger objects like salt molecules to move freely through it.

But what is an area of lower and higher concentration of water? It simply means that in a low level of water there is a higher level of solutes like salt and sugar. And the higher concentration area has no or fewer solutes in it. So all we need to remember is that the water has the natural tendency to move through the higher to the lower concentration area.

For example, we have glass tank with a partition in the centre made up of semi-permeable membrane that can allow the solvents like water to pass through it but not larger particles of solutes like salt and sugar. Now fill this tank with some fresh water on both the sides. Let’s call it A and B. You will find that those water molecules are moving, as they like to move. We can see that these water molecules moving but the net movement on both the sides are zero meaning the overall change in the direction of flow is zero. Now let’s sprinkle some salt on side B. Salt particles are too large to pass through this membrane so it will stay on this side.

Which direction the water will flow A or B? It will move from side A to side B as this side has higher solutes and higher solutes mean low concentration of water.

Did you know, some organs including the kidneys rely on the Osmosis? The kidney’s task is to filter waste products from the blood and excrete them as urine. Each kidney contains more than a million microfilters called Nephrons which allow small particles, such as water, glucose, urea and ions, to pass through it while excluding the blood molecules themselves. After this filtration takes place the kidneys must reabsorb enough water to maintain a healthy balance in the blood plasma. They do this by Osmosis.