|MadSci Network: General Biology|
Spreading of molecules in gaseous or in colloidal form is purely based on dispersion mechanism. When the molecules are inhaled, they are partly absorbed in the lung and also in the nose, which leads to sensing by the cells. It is possible to clear off the smell by exhaust. Although inhaling the smell clears off the molecules, the quantity thus cleared is very less as the spread continues in the atmosphere. Further, only a fraction of the molecules inhaled is absorbed. However, after a while, the sensory cells may get saturated with the smell and we may feel that there is no smell or the same is reduced. Dilution by diffusion also helps for this. Our system knows better, whether the ambience we live in is good or bad. Even if you are inhaling fragrance, prolonged inhalation may lead to headache. Respond to the body signals and obey its demands to get rid of it with no regards on the source.
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