TRANSPIRATION PULL THEORY
Transpiration Pull Theory was proposed by Dixon and Jolly, It states that
During transpiration, water escapes through stomata present on leaf, this loss of water is substituted by evaporation from mesophyll cells. This drops the water potential of mesophyll cell, causing them to take water from neighboring cells. As a result of which a potential gradient develops which extends up to xylem sap. This creates a tension, in xylem elements of leaf which is transmitted to different other xylem element present in stem and root. Thus, water flow in a channel, which is held together by cohesion and adhesion force and keeps the water column in the place.