In the cross section Arundo donax, the epidermis shows a regular pattern of normal epidermal cells which are small and thick walled interspersed with clear oval-shaped silica cells. Several layers of parenchyma cells are found immediately under the epidermis.
These cells contain the filler or backing. This tissue can be found in all parts of the plant. Herbaceous plants are mainly made up of this tissue. In this region the parenchyma cells are relatively small and thick walled in contrast to the large thin walled parenchyma cells found in the inner region of the stem.
Cross Section
1. epidermal cell.
2. silica cell in epidermis.
3. small thick-walled parenchyma cell in outer region of stem.
4. large thin-walled parenchyma cell in inner region of stem.
5. thickwalled fiber cell in cylindrical band near outer region of stem.
6. small vascular bundle within cylindrical band of fiber cells.
7. large vascular bundle in inner region of stem.
8. ring of fiber cells surrounding vascular bundle.
9. food conducting cell of phloem
10. water conducting cell of xylem.
2. silica cell in epidermis.
3. small thick-walled parenchyma cell in outer region of stem.
4. large thin-walled parenchyma cell in inner region of stem.
5. thickwalled fiber cell in cylindrical band near outer region of stem.
6. small vascular bundle within cylindrical band of fiber cells.
7. large vascular bundle in inner region of stem.
8. ring of fiber cells surrounding vascular bundle.
9. food conducting cell of phloem
10. water conducting cell of xylem.