Hypotheses, Theories and Models of and about Plants


  • Jan Baptista van Helmont
    • An incorrect conclusion that water, on its own, makes plants grow.
  • John Priestly
  • Jan Ingenhousz
  • Jean Senebier

Transpiration-cohesion-tension Theory

  • Water in the xylem is pulled upwards
  • Creates negative pressure, i.e. tension
  • Tension extends from leaves to roots
  • Transpiration’s effect on water = straw