Explain Cohesion-Tension Theory

Transpiration of water through stomata creates low potential at the top of the xylem. Water molecules stick together via hydrogen bonds in a process known as COHESION. This occurs because water molecules are polar with a 𝛿+ and 𝛿- end. Water is then pulled up the xylem creating TENSION. It is as though water molecules are "sucked" up to the leaves (like a straw).

JM

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