1. Unicellular root hairs which are tubular extensions of epiblema cells absorb readily available capillary water from soil. 

2. The three physical processes imbibition, diffusion and osmosis are concerned with absorption of water. 

3. Water molecules get adsorbed on cell wall of root hair (imbibition). 

4. They enter the root hair cell by diffusion through cell wall which is freely permeable. 

5. By process of osmosis they enter through plasma membrane which is semipermeable. 

6. The root hair cell becomes turgid and hence its turgor pressure increases and D.ED. value decreases. 

7. The adjacent cell of cortex has more D.ED. value as its osmotic potential is more. 

8. The cortical cell thus takes water from epidermal cell which is turgid. This process goes on due to gradient of suction pressure developed from cell to cell till thin walled passage cells of endodermis. 

9. From endodermis it will enter pericycle and then due to hydrostatic pressure it is forced in protoxylem cell. 

10. The pathway of water is by apoplast and symplast. 

11. When water passes through cell wall and intercellular spaces of cortex it is apoplast pathway. 

12. When water passes across living cells through their plasmodesmatal connections it is symplast pathway.