Page 66 - PG 101-Course notes مذكرة النظري 24-25 with spec

Medicinal plants (PG 101) Level 1 Clinical Pharmacy-PharmD

B) Vessels

 Vessels are narrow or wide water conducting tubes, formed from B) Xylem parenchyma
number of cells, by a partial or complete disintegration of their end ▪ Living cells,
walls. (perforated end walls) scattered among

They may be: tracheary elements
a-Protoxylem (narrow) (annular- spiral) and fibers or
b-Metaxylem(wide) (reticulate - bordered pitted) aggregate into rays.
▪ Thin walled but often
with lignified walls.

Reticulate ▪ Function: storage
and conduction of
Spiral vessels
materials across the
vessels tracheary elements.

Bordered
Annular pitted

vessels vessels

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