Tree Biology

Contents: - periderm - phellem - cork cambium - phelloderm - cortex - phloem- phloem rays - phloem - 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 - decay development

Click on any of the above terms to view its location in the tree cross section

Apoplast is the dead cells and empty space that surround the symplast. The apoplast is typically comprised of the vessels (deciduous hardwoods) or tracheids (conifers) and fibers.