BharatNotes Osmosis
noun (uncountable)Usage in a UPSC answer
The process of osmosis underpins renal water reabsorption in the loop of Henle, a mechanism directly relevant to understanding kidney disease burdens that affect over 17% of India's adult population.
Synonyms
Antonyms
Word Family
osmotic (adjective), osmotically (adverb), osmoregulation (noun), osmoregulate (verb)
Root
Greek ōsmos = push, thrust; from ōthein = to push
Etymology
Derived from Modern Latin osmosis, coined in the mid-19th century from Greek ōsmos (a push or thrust), itself from ōthein (to push). The Scottish chemist Thomas Graham first described the principle in 1854, and the term was formalised by Wilhelm Pfeffer in 1877. The word entered biological and chemical science to describe the directional movement driven by concentration gradients.
Memory Hook
Think of osmosis as water being 'pushed' (Greek ōthein = push) toward the crowd — water always moves toward where solutes are denser, just as crowds draw more people in. Picture a crowd of salt molecules pulling water molecules across a membrane barrier.
How This Word Works in UPSC Writing
The movement of solvent, usually water, across a semi-permeable membrane from a region of lower solute concentration to one of higher concentration. Its GS3 application is water treatment, since reverse osmosis drives water the other way under applied pressure and is the basis of desalination and much domestic purification. The trade-off worth naming is that reverse osmosis is energy-intensive and produces a concentrated brine that must itself be managed.
Don’t Confuse It With
Osmosis moves solvent across a semi-permeable membrane down its concentration gradient. Diffusion is the movement of solute particles from higher to lower concentration. Reverse osmosis forces solvent against the gradient using applied pressure. Active transport moves substances against a gradient using cellular energy.
Hindi Meaning
परासरण (parāsaran); विपरीत परासरण is reverse osmosis.
Common Questions
- What is osmosis?
- The movement of water across a semi-permeable membrane from a region of lower solute concentration to one of higher concentration.
- What is reverse osmosis used for?
- Applying pressure to force water against the concentration gradient, which is the basis of desalination and of most domestic water purifiers.
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