The name given to the xylem and phloem structures in a plant’s stem is called

The xylem and phloem always lie adjacent to each other (Figure 3). In stems, the xylem and the phloem form a structure called a vascular bundle; in roots, this is termed the vascular stele or vascular cylinder.

this protocol provides a detailed procedure for nucleoprotein extraction from cultured cells and tissues in an efficient manner.