Absorption of water: The higher plants absorb water from soil by their root hairs. Root hair region is termed as absorption region. Unicellular root hairs are specially modified epidermal cell for absorption of water. Cell walls of root hairs are made of cellulose and thus it is permeable. Beneath the cell wall, there is the cell membrane, which is selectively permeable.
Inside the root hair the cell sap is concentrated and in the outside there is water in between soil particles. So water from soil enter into the cell through permeable cell wall and selectively permeable cell membrane by osmosis. Afterwards this water from root hair reaches the vessels of xylem tissue by cell-to-cell osmosis. From vessels the water moves to leaves.