http://crystal.uah.edu/~carter/osmosis/plasmoly.htm
(A) Plasmolysis occurs when a plant cells membrane shrinks
away from its cell wall. This phenomenon occurs when water is
drawn out of the cell an into the extracellular (outside cell) fluid.
The movement of water occurs across the membrane moving from
an area of high water concentration to an area of lower water
concentration outside the cell.
(B) Plant cells where the water flow into the cell and out of the
cell are in equilibrium are not capable of providing the cell with
support. Flaccid is a term used to indicate that the cell, although
it contains water, does not have enough internal turgor pressure
to provide structural support.
(C) As mentioned earlier, turgor pressure is the buildup of water
within the plant cell. Because of the rigidity of the cell wall, the
cell does not rupture, but instead the internal pressure
increases. This increased internal pressure gives the plant cells
structure that can support the plant.