What is not part of a plant’s apoplast among the cell wall of a root hair, the cell wall of a transfer cell, the cell wall of a mesophyll cell, the lumen of a sieve tube?

The lumen of a sieve tube.-much of the water and ions that soak into a plant root remain in the walls of the cortex cells and move toward the stele along an extracellular pathway known as the apoplast. at the endodermis, that extracellular pathway is blocked since each endodermal cell has a waxy belt in its wall called a casparian strip, which is impervious to water and dissolved minerals, thereby blocking the apoplast, between the cortex and the stele. water and minerals that make it to the endodermis along the apoplast can enter the stele only by crossing the plasma membrane of an endodermal cell, and passing through the plasmodesmata.