ABSTRACT
Research has progressed steadily since, and histogenesis and the structure and functions of the xylem and phloem continue to be fascinating aspects of the study of plant anatomy and physiology. The histogenesis of conducting tissues and of the xylem in particular is a difficult process to capture in its spatio-temporal dynamics. The differentiation of a cell derived from divisions of the cambial continuum into a conducting element is of short duration, some hours to a few tens of hours when the spring tissue forms in Angiosperms. It begins with a growth phase, principally in length in the primary xylem and in diameter in the secondary xylem. The water rising through the wood vessels of the trunk and branches reaches the shoots and leaves, passing laterally through the network of the primary xylem. The functional continuity of the xylem (and phloem) originates in the functional continuity of the cambial meristem.
