Answer: Hydathodes.
- A Hydathodes
- B Stomata
- C Lenticels
- D Ostioles
Correct answer: A. Hydathodes
Explanation: Guttation releases liquid water at leaf tips and margins through hydathodes, driven by root pressure.
Water can travel through cell walls (apoplast) or cell-to-cell through the cytoplasm (symplast) - but the Casparian strip at the endodermis blocks the apoplast route entirely, forcing everything through a selectively permeable membrane (symplast) before it can enter the xylem.
Concept context
Water and mineral absorption, the ascent of sap, transpiration, and phloem transport via the pressure flow hypothesis.