The transport of ions up the stem to all parts of the plant is through:

$A -$ $A$ plant adjusts the quantity and types of solutes that reach the xylem.
$R -$ Transport proteins of endodermal cells are control points.

Minerals absorbed by the roots travel up the xylem. How do they reach the parts where they are needed most? Do all the parts of the plant get the same amount of the minerals?

Solutes are absorbed by a plant cell through

Transport of minerals through xylem is

The chief sinks for the mineral elements in plants are: