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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.
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 ...
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 ...
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
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 .
Petrified wood forms when woody stems of plants are buried in wet sediments saturated with dissolved minerals. The lack of oxygen slows decay of the wood, allowing minerals to replace cell walls and to fill void spaces in the wood. [2] [1] Wood is composed mostly of holocellulose (cellulose and hemicellulose) and lignin. Together, these ...
The wood moisture content is above 25% on a dry-weight basis; The environment is sufficiently warm; Oxygen (O 2) is present; Wood with less than 25% moisture (dry weight basis) can remain free of decay for centuries. Similarly, wood submerged in water may not be attacked by fungi if the amount of oxygen is inadequate. Fungi lumber/timber ...
Carbohydrates that are composed of carbon, hydrogen, and oxygen and range in complexity from relatively simple sugars to large molecules of cellulose. Fats that are composed of glycerids of fatty acids, like butyric, stearic, and oleic. They also include carbon, oxygen, and hydrogen. Lignins are complex compounds from the older wood parts. They ...