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		II. Water transport in plants A. Long range The basic pattern of water movement in a plant is: soil [!]root[!]vascular tissue [!]leaf[!]atmosphere
					36.1
		1. Absorption Most absorption of water and minerals occurs near the tipsof the roots, where the root hairs increase the surface area. 2. Lateral transport36.6 Once water has been absorbed out of the surrounding soil, it has to be transported to the vascular tissue. This movement is predominantly radial, straight towards the center. a. Symplast vs apoplast In principle there are 3 ways that water could move through a root tightly packed with cells: (1) across the plasma membrane into 1 cell, across the PM out of that cell, and then into the next - it is unlikely that a water molecule will move entirely by this mechanism because the other 2 routes are quicker (2) into one cell, then across the plasmodesmata into the next - symplast (3) around the cells through the "soggy paper" cell walls - apoplast Most water molecules probably travel through the cortex of the root moving back and forth between the symplast and the apoplast
		b. Root anatomy Water moves through the root from [!] soil [!]epidermis[!]root cortex [!]root stele [!]xylem [!] Casparian strip			36.6
		When it moves between the cortex and the stele it encounters the Casparian strip