Uptake and transport of Mineral Nutrients:

à Uptake of mineral ions:- All the minerals can’t be taken by roots because of :

1. The mineral conc. in soil is lower than that in roots.
2. Cell membrane doesn’t allow the passage of some minerals which are present in form of ions.

Thus, mostly minerals enter in root epidermis by the process of active absorption (in which ATP molecules are consumed) plant adjusts quantity and types of solutes in the transportation proteins of endothermal cells that reach the xylem specific proteins present in root hair cell’s membrane actively pumps ions from soil into cytoplasm of endothermal cells.

The presence of transport protein in plasma membrane let some ions cross it.

Root endodermis is able to transport ions into one direction because of the presence of suberin.

à Translocation of Minerals Ions:

Translocation stream transport ions after reaching xylem mineral elements are mostly transported to growing regions like young leaves, developing flowers, fruits and seeds, apical and lateral meristems and to storage organs.

Older leaves export their mineral contents to younger leaves easily mobilized elements are sulphur, phosphorus, potassium and phosphorus. Calcium can’t be remobilized because they are structural components.

Nitrogen travels as inorganic ions in form of amino acids and related compounds.

 Some small amount of exchange of material also takes place b/w xylem and phloem.