Johann Jacob Paul Moldenhawer (11 February 1766 - 21 August 1827) was a German botanist who made a number of important discoveries in plant anatomy. February 11 is the 42nd day of the year in the Gregorian Calendar. ... 1766 was a common year starting on Wednesday (see link for calendar). ... August 21 is the 233rd day of the year (234th in leap years) in the Gregorian calendar. ... Naval Battle of Navarino by Carneray 1827 was a common year starting on Monday (see link for calendar). ... Botany is the scientific study of plant life. ... Plant anatomy or phytotomy is the general term for the study of the structure of plants. ...

He was born in Hamburg, the son of a minister, and started out studying theology and the classics. At some unknown point he became interested in plants, and in 1791 he published Tentamen in historiam plantarum Theophrasti, on Theophrastus, and the following year he is recorded as "Extraordinary Professor of Botany and Fruit Tree Culture" (außerordentlicher Professor für Botanik und Obstbau) at the University of Kiel. He studied plant anatomy from 1795 until 1812, when he published Beyträge zur Anatomie der Pflanzen on his results. Immediately subsequently he concentrated on fruit tree culture. He died in Kiel. Hamburg from above Hamburgs motto: May the posterity endeavour with dignity to conserve the freedom, which the forefathers acquired. ... Theophrastus (Greek Θεόφραστος, 370 — about 285 BC), a native of Eressos in Lesbos, was the successor of Aristotle in the Peripatetic school. ... The University of Kiel, in full the Christian-Albrechts-Universität zu Kiel (in short: CAU), is a university in the city of Kiel, Germany. ... A plum tree Flowering almond tree A fruit tree is a tree bearing fruit — the structures formed by the ripened ovary of a flower containing one or more seeds. ... Kiel ( ) is a city in northern Germany and the capital of the Bundesland Schleswig-Holstein. ...

Moldenhawer's contributions center around the microscopic examination of plant tissues, for which he devised techniques to separate the cells from the middle lamella separating them. He identified vascular and parenchymatous tissues, described vascular bundles, observed the cells in the cambium, and interpreted tree rings. He found that stomata were composed pairs of cells, rather than a single cell with a hole. Although Moldenhawer is not credited with the cell theory, his work provided key documentation for the validity of the theory in plants. Vascular is an adjective for the word vessel and refers to tube-like structures. ... Vascular cambium is a tissue found in the stems of perennial dicots. ... Pinus taeda Cross section showing annual rings Cheraw, South Carolina Dendrochronology or tree-ring dating is the method of scientific dating based on the analysis of tree ring patterns. ... This is not about surgically created bowel openings; see stoma (medicine) In botany, a stoma (also stomate; plural stomata) is a tiny opening or pore, found mostly on the undersurface of a plant leaf, and used for gas exchange. ... A prokaryote, a simple cell Cell theory is a scientific theory that is one of the foundations of biology. ...

The genus Moldenhawera is named in his honor.

References

• Duane Isely, One hundred and one botanists (Iowa State University Press, 1994), pp. 127-128