Q. Which of the following statements is/are true? I.The apoplastic movement of water occurs exclusively through the cell wall without crossing any membranes. II.Solutes present in a cell (or in any solution) increase the free energy of water or water potential. III.The symplastic movement occurs from cell to cell through the plasmodesmata. IV.Membrane permeability depends on the membrane composition, as well the chemical nature of the solute.
Explanation
In apoplast pathway, water passes from root hair to xylem through the walls of intervening cells without crossing any membrane or cytoplasm. Water potential of pure water at atmospheric pressure is 0 Mpa, addition of solutes reduce water potential (to a negative value). In symplast pathway, water passes from cell to cell through their protoplasm. It does not enter cell vacuoles. The cytoplasms of the adjacent cells are connected through bridges called plasmodesmata. Membrane permeability is the ability of a membrane to allow passage of gases, liquids, solutes (dissolved substance) through it. It is depend upon two factors- nature of membrane (membrane composition) and nature of passing substance.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.