Osmosis Flashcards
What is osmosis
Osmosis is the movement of water from a less concentrated solution to a more concentrated solution through a partially permeable membrane.
This is shown in the animation above. Eventually the level on the more concentrated side of the membrane rises, while the one on the less concentrated side falls. When the concentration is the same on both sides of the membrane, the movement of water molecules will be the same in both directions. At this point, the net exchange of water is zero and there is no further change in the liquid levels.
Osmosis in animal cells
Osmosis explains how water moves in and out of animal cells through the cell membrane. If water continues to leave a cell it will shrink and become crinkly. If water continues to enter a cell it will eventually burst. These things happen because animal cells are not surrounded by an inelastic cell wall, unlike plant cells.
Osmosis in plant cells
Plant cells are enclosed by a rigid cell wall. When the plant cell is placed in a hypotonic solution , it takes up water by osmosis and starts to swell, but the cell wall prevents it from bursting. The plant cell is said to have become “turgid” i.e. swollen and hard.
