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Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants.It is an organic material – a natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that resists compression.
The database thousands of wood anatomical descriptions and nearly 66,000 photomicrographs of contemporary woods, along with more than 1,600 descriptions and 2,000 images of fossil woods. [ 16 ] Another very important database for wood anatomy, is the so-called, Delta Intkey .
Wood ash from a campfire. Wood ash is the powdery residue remaining after the combustion of wood, such as burning wood in a fireplace, bonfire, or an industrial power plant.It is largely composed of calcium compounds, along with other non-combustible trace elements present in the wood, and has been used for many purposes throughout history.
An example of this is that secondary wall in wood contains polysaccharides called xylan, whereas the primary wall contains the polysaccharide xyloglucan. The cells fraction in secondary walls is also higher. [7] Pectins may also be absent from the secondary wall, and unlike primary walls, no structural proteins or enzymes have been identified. [4]
Wood chemistry, whose primary focus is the analysis of the chemical constituents comprising wood, with specific emphasis on cellulose, lignin, hemicelluloses, and extractives, as well as on the various products derived from these components. It is also explores potential uses for pulp and paper production, the utilization of wood and wood waste ...
There are two main natural forces responsible for causing defects in timber and lumber: abnormal growth and rupture of tissues. Rupture of tissue includes cracks or splits in the wood called "shakes". "Ring shake", "wind shake", or "ring failure" is when the wood grain separates around the growth rings either while standing or during felling.
A section of rosemary stem, an example of a woody plant, showing a typical wood structure. A woody plant is a plant that produces wood as its structural tissue and thus has a hard stem. [1] In cold climates, woody plants further survive winter or dry season above ground, as opposed to herbaceous plants that die back to the ground until spring. [2]
Its most commonly noted function is the support through strengthening of wood (mainly composed of xylem cells and lignified sclerenchyma fibres) in vascular plants. [ 17 ] [ 18 ] [ 19 ] Finally, lignin also confers disease resistance by accumulating at the site of pathogen infiltration, making the plant cell less accessible to cell wall ...