Home > Tree biology > Compannion cells

Tree biology

Contents: - periderm - phellem - cork cambium - phelloderm - cortex - phloem- phloem rays - sieve tube element - companion cells - cambial zone (cambium) - bark - xylem - growth ring - vessels - tyloses - parenchyma - axial parenchyma - multiserrate ray parenchyma - uniserrate ray parenchyma - fibers - symplast - apoplast - growth ring/ray compartment - wounding response - decay development

Select any of the above terms to view its location in the tree cross section. Text at bottom.

Companion cells are alive and contain a nucleus. They are located adjacent to sieve tube elements which do not contain a nucleus. Companion cells help the sieve tubes function in moving sugars from leaves toward roots.

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