How do the apoplast and symplast system work together in transporting water through the plant?

Question

In which tissue do they actually lie?

I can't make myself a clear picture of how these two systems are arranged in the cell and how they work. Visual explanation if possible please...:-)

Answer 1

Plants move water through osmosis

apoplast = lies between plant cells and the plant cuticula

.  apoplastic route facilitates the transport of water and solutes across a tissue or organ.

more pictures:  http://images.google.com/images?gbv=2&hl...

symplast = is in the inner side of the plasma membrane

.  The symplast of a plant is the inner side of the plasma membrane in which water can freely diffuse.

More pictures:  http://images.google.com/images?gbv=2&hl...

According to Wikipedia:  http://en.wikipedia.org/wiki/Apoplast

"Within a plant, the apoplast is the free diffusional space outside the plasma membrane. It is interrupted by the Casparian strip in roots, air spaces between plant cells and the cuticula of the plant.

Structurally, the apoplast is formed by the continuum of cell walls of adjacent cells as well as the extracellular spaces, forming a tissue level compartment comparable to the symplast. The apoplastic route facilitates the transport of water and solutes across a tissue or organ. This process is known as apoplastic transport"

According to Wikipedia:  http://en.wikipedia.org/wiki/Symplast

"The symplast of a plant is the inner side of the plasma membrane in which water (and low molecular solutes) can freely diffuse.

The plasmodesmata allow the direct flow of small molecules such as sugars, amino acids and ions between cells. Larger molecules can also be transported through with the help of actin structures.

This allows direct cytoplasm to cytoplasm flow of water and other nutrients along concentration gradients. It is particularly used in the root systems to bring in nutrients from soil. It moves these solutes from epidermis cells through the cortex into the endodermis and eventually the pericycle where it can be moved into the xylem for long distance transport. It is contrasted with the apoplastic flow which uses cell wall transport."

The articles have a picture:  http://en.wikipedia.org/wiki/Image:Apopl...

According to Wikipedia:  http://en.wikipedia.org/wiki/Osmosis

"Osmosis is the diffusion of a solvent (frequently water) through a semi-permeable membrane, from a solution of low solute concentration (high water potential) to a solution with high solute concentration (low water potential), up a solute concentration gradient. It is a physical process in which a solvent moves, without input of energy, across a semi-permeable membrane (permeable to the solvent, but not the solute) separating two solutions of different concentrations. Osmosis releases energy, and can be made to do work, as when a growing tree-root splits a stone."