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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.


The xylem is the wood of the tree generated to the interior of the cambial zone. The outer portion is conducting sapwood that stores starch and conducts water and substances dissolved in water. The inner portion is non-conducting sapwood that stores starch. Interior to the non-conducting sapwood in many trees is heartwood.