Define the following terms:
$(1)$ Mobilised elements
$(2)$ Immobilised elements

(N/A) $(1)$ Mobilised elements: These are mineral elements that are actively mobilised within the plants,moving from older,senescing parts to young,developing tissues.
$(2)$ Immobilised elements: These are mineral elements that are relatively immobile and are not transported out of mature organs to younger tissues,often becoming structural components of the cell.