c. Root pressure is a force or the hydrostatic pressure generated in the roots that help in driving the fluids and other ions from the soil in upwards directions into the plant's vascular tissue - Xylem. Required fields are marked *. Adhesion

d. Cohesive and adhesive properties of water molecules- Cohesion is the mutual attraction between water molecules. Cohesion (with other water molecules) and adhesion (with the walls of xylem vessels) helps in a continuous flow of water without breaking the column. Salts and minerals must be actively transported into the xylem to lower it's water potential. Both root pressure and transpiration pull are forces that cause water and minerals to rise through the plant stem to the leaves. You apply suction at the top of the straw, and the water molecules move toward your mouth. Round clusters of xylem cells are embedded in the phloem, symmetrically arranged around the central pith. Vital Force Theories . Thecohesion-tension model works like this: Here is a bit more detail on how this process works:Inside the leaf at the cellular level, water on the surface of mesophyll cells saturates the cellulose microfibrils of the primary cell wall. To understand how these processes work, we must first understand the energetics of water potential. On the other hand, transpiration pull is the force developing in the top of the plants due to the evaporation of water through the stomata of the mesophyll cells to the atmosphere. 2 Explain transpiration pull theory for ascent of sap. IBO was not involved in the production of, and does not endorse, the resources created by Save My Exams. For this reason, the effects of root pressure are mainly visible during dawn and night. This is called sap exudation or bleeding. Osmosis.