Solution:

The identification of the forms and modes of mineral transport in plants was aided by an examination of xylem exudates. For example, an examination of xylem exudates found that the majority of nitrogen is delivered as organic molecules rather than inorganic molecules. Phosphorus and Sulphur are transferred in small amounts as organic molecules. Between the xylem and the phloem, there is some material exchange. As a result, it’s impossible to say that xylem solely transports inorganic substances while phloem only transports organic molecules.