An additional apoplastic route that allows direct access to xylem is along the secondary roots because they ______.

Secondary roots (lateral roots) originate from the pericycle, which is a layer of cells located just inside the endodermis.

As these secondary roots grow outward, they break through the endodermis and its Casparian strip.

This disruption creates a gap in the endodermal barrier, providing an additional apoplastic route that allows water and solutes direct access to the xylem, bypassing the Casparian strip.

Answer: develop from pericycle