Question

differentiate between transpirational pull and capillary action

Answer 1

Transpirational pull is the main driving force by which plants absorb water through roots. It is the suction pull created by the loss of water through the tiny pores called stomata present in the leaves in the form of water vapours. In actively growing plants, water evaporates continuously from the mesophyll cells of the leaf creating a negative pull. The lost water in the mesophyll is replaced by the absorption of water from the adjacent cells. Now water starts to pull through xylem vessels of leaves. Xylem vessels of leaves pulls water from xylem of stem which take water from Xylem of roots. Thus, water flow in a continuous column.

Capillary action is the property of liquid like water to flow in narrow spaces. It is the result of forces of cohesion (water molecules attract each other) and adhesion (water molecules are attracted and stick to wall of tube).