Oxygen Supply for Single-Celled Organisms: Diffusion vs. Osmosis Explained

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Homework Statement


Is the oxygen required by the single-celled organisms obtained by diffusion or osmosis through the surface membrane of the cell?

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The Attempt at a Solution


I'm thinking osmosis since there's a membrane through which the oxygen passes. But I've been looking at definitions of osmosis and some talk of osmosis is only to do with water moving from high to low concentration. Diffusion is about any molecule moving anywhere.

Bit confused. Please advise. Thank you
 
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You are right
Diffusion is in all states of substances
Osmosis is usually confined to solutions ;)
 
The book I'm reading said oxygen required by the single-celled organisms diffuses across the surface membrane of the cell? I wasn't convinced that was accurate because there's a membrane involved so must be osmosis. But definitions I read about osmosis talk only of osmosis of water across a membrane. But I'm talking of oxygen (not water) so it :
"osmosis of oxygen (NOTE : no need to mention the word membrane because it is assumed a membrane exists in osmosis)" or "diffusion of oxygen across a membrane".
 
Osmosis is a term that refers exclusively to the diffusion of solvent molecules (in most cases, water) across a semi-permeable membrane. The spontaneous crossing of all other substances across a membrane would be referred to as diffusion.
 
Ygggdrasil said:
Osmosis is a term that refers exclusively to the diffusion of solvent molecules (in most cases, water) across a semi-permeable membrane. The spontaneous crossing of all other substances across a membrane would be referred to as diffusion.

Thanks. Thats cleared by confusion. Osmosis is the diffusion of the liquid molecules across a membrane (in the body it would be water but in chemistry could be anything e.g an alcohol) in which the substrate (in this case oxygen) is dissolved. The substrate diffuses across the membrane