- A Bulk flow driven by transpirational pull, bypassing active transport in typical laboratory settings
- B Diffusion down a concentration gradient, with little active uptake as generally observed
- C Active uptake by root hair cells, then movement via symplast or apoplast to the xylem
- D Osmosis of dissolved minerals along the water potential gradient under usual circumstances
Correct answer: C. Active uptake by root hair cells, then movement via symplast or apoplast to the xylem
Explanation: Minerals are actively absorbed (often against a concentration gradient) by root hair cells using energy-dependent transporters, then move radially through the symplast or apoplast (interrupted by the Casparian strip) into the xylem.
Concept context
Water and mineral absorption, the ascent of sap, transpiration, and phloem transport via the pressure flow hypothesis.