Water Absorbing System

Plants have the ability to absorb water from the entire surface like root, stem, leaves, etc. The main source of water for plants is soil. Therefore the root system in plants plays major role in the absorption. Roots are normally very extensive and grow rapidly in the soil. In roots the most efficient part for the absorption of water is root hair zone. This root hair zone has thousands of the minute root hairs which are actively takes part in the absorption. 

There are two pathways in which water passes from root hair zone to xylem inside the roots :-

a) Apoplast Pathway:- In this pathway water moves from root hair zone to xylem through the walls of intervening cells without crossing the  membranes of cells. Therefore in this pathway plants utilizes very less amount of energy because in this pathway there is very less hindrance for passage of water. However this movement of water if interrupted at one place i.e casparian stripes present in endothermal cells.  

Symplast pathway:- This type of pathway is also called transmembrane pathway. In this pathway water has enter into the protoplasm without entering into the vacuoles. The cytoplasm of the adjacent cells are connected through plasmodesmata  ( the bridge between two cells ). For entering into the symplast , water has to pass through the plasmamembrane. This type of absorption involve the expenditure of energy and therfore slower than the apoplastic movements.