[Campbell Biology P.843] Which statement best summarizes the primary difference in how xylem... | Practice Question

Which statement best summarizes the primary difference in how xylem sap ascends according to root pressure versus the cohesion-tension hypothesis?

  • A: Root pressure is the main force, while cohesion-tension is a minor contributor.
  • B: Root pressure actively pushes sap, whereas cohesion-tension creates a pull.
  • C: Root pressure relies on transpiration, but cohesion-tension relies on guttation.
  • D: Cohesion-tension is only significant in short plants, while root pressure is for tall plants.

Explanation

The text clearly states that root pressure is a 'minor mechanism driving the ascent of xylem sap, pushing water,' while the cohesion-tension hypothesis explains that 'transpiration provides the pull for the ascent of xylem sap.'