Osmosis is the movement of a Solvent like Water through a Membrane.

The Plasmalemma is permeable to Water which is a Solvent.

The Plasmalemma is a barrier to the movement of Solutes.

It is permeable to small, uncharged molecules.

Its is relatively impermeable to large molecules and charged molecules like ions. These require special membrane transport proteins to cross the Plasmalemma and other membranes.

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The driving forces for Osmosis are concentration gradients and
pressure gradients.

The Total Driving Force for Osmosis is called the Water Potential.

Movement will occur from areas of High Water Potential towards areas of
Low Water Potential.

This is set at 0.

Addition of Solute lowers the Water Potential which will have a negative value.

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The movement of Water across biological membranes occurs as single molecules which pass through the membrane & as many molecules that cross the membrane through Water-Selective Pores.