Ultratrace elements storage

Active transport - the accumulation within, or the extrusion from, a cell of an element in opposition to a concentration gradient. Active transport is saturable, is energy dependent and involves a carrier protein that usually is quite specific for an element. The mechanisms of absorption for the various ultratrace elements are given in Table 1 this table also lists the known transport and storage vehicles for these elements. 

Table 1 Absorption, transport, and storage characteristics of the ultratrace elements...

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