Osmosis - Partially Permeable Membrane (D-C)

 •Diffusion of water across a partially permeable membrane

 •Diffuses from a high concentration of water to a low concentration of water

 Partially Permiable membrane:

 •Millions of small holes 

 •Only allows small molecules (like water) to pass through

 •Large molecules like glucose, bounce away


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Osmosis - Why does it happen? (B-A*)

 •Due to the random movements of molecules in a solution 

 •Molecules bump into a hole in the wall- water will move through, glucose (and other molecules) will bounce back

 •The more dilute the solution, the more water there is. 

 •Dilute solution - more water - higher chance of Osmosis

 •Water always flows toward the more concentrated solution


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Sports drinks (brief) (B-A*)

 •Are isotonic

 •Isotonic - has the same concentration as blood

 •Contains sucrose - replaces substances used in respiration

 •Contains water and ions - replaces substances lost from sweating

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Osmosis - Cells (D-C)

 •Animal cell - cell will become turgid if put in a solution more dilute than the cytoplasm

 •Animal cell - cell will become flaccid if put in a solution more concentrated  than the cytoplasm

 •Plant cell -  cell wall will push against the cell wall if put in a solution more dilute than the cytoplasm

 •Plant cell - cell wall will pull away from the cell wall if put in a solution more concentrated than the cytoplasm 

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Osmosis - Plant Cell Walls (B-A*)

 •Cell wall - prevents the plant cell from bursting

 •Cell wall - prevents the plant from collapsing due to no water. 

 Cell wall - is strong enough to maintain the shape of the cell if the cell membrane pulls away from it

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