Osmosis: The Movement of Water
Understanding water potential and partially permeable membranes
Core Definition
Water diffuses through partially permeable membranes by osmosis.
Supplement Definition (The Scientific One)
Osmosis is the net movement of water molecules from a region of higher water potential (dilute solution) to a region of lower water potential (concentrated solution), through a partially permeable membrane.
Examiner Trap Alert!
Students often write "water moves by osmosis" and lose marks. Always include the DIRECTION: "Water enters the cell by osmosis" or "Water moves from dilute to concentrated solution by osmosis."
Breaking It Down (Baby Steps)
Water molecules (small) and solute molecules like sugar (big)
Partially permeable membrane with tiny holes
Water can pass through, large solutes cannot
Water moves to balance concentrations
Key Keywords to Remember
Master the Keywords: Osmosis Checklist
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