Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Tissues, cellulose-containing

The whole of a multi-cellular organism is contained by outer cell layers, which are described in biology texts, and maintained by connective tissue. Connective tissue is a novel, external biopolymer structure of multi-cellular organisms found within their new extracellular, circulating fluid compartments (see Section 8.9). As mentioned there, the main connective tissues, covalently cross-linked structures, are (1) those of plants, celluloses (polysaccharides), often cross-linked by lignin (2) those of lower animals and insects, mixed cross-linked polysaccharides and... [Pg.351]

The first pH sensor was developed at NIH (Bethesda, Maryland) and made use of phenol red as acid-base indicator, covalently bound to polyacrylamide microspheres10 such microspheres are contained inside a cellulose dialysis tubing (internal diameter 0.3 mm) connected to a 250 pm plastic fibre (Figure 2). The probe was inserted into either the tissue or the... [Pg.419]

Cellulose is a high molecular weight polymer of D-glucose with fi( 1 -4)-glycosidic bonds, found in plant fibres it is the major component of most plant tissues. Starch is another common polysaccharide, containing two polymers of glucose, amylose and amylopectin. It was used in some paint preparations and in the production of paper. Acid treatment of starch produces dextrins, which are used as adhesives and additives in water colour paintings. [Pg.20]

More complex polysaccharides play important roles in connective tissues and elsewhere. For example, hyaluronic acid is universally present in connective tissues of animals, as well as in their vitreous and synovial fluids. It helps to provide the fluids present in joints with shock-absorbing and lubricating properties. Unlike cellulose, chitin, starch, and glycogen, hyaluronic acid contains two different monomers glucose and N-acetylglucosamine alternate in the structure. Thus, hyaluronic acid is a regular alternating copolymer ABABABA —... [Pg.211]

The detailed distribution of polysaccharides within cell walls can be determined by immunolabeling sections of plant tissues with appropriate antibodies (Knox, 2008). Such studies also show the distribution of polysaccharides in the middle lamella (Figure 3.5), which develops from the cell plate, formed at cell division, and is responsible for cell-cell adhesion. Cell comers (tri-cellular junctions) and the comers of the intercellular spaces can be regarded as extensions of the middle lamella. They are where stresses that tend to separate plant cells are concentrated and have been referred to as reinforcing zones (Jarvis et al., 2003). These zones and the middle lamella are rich in pectic polysaccharides, but contain no cellulose microfibrils (Jarvis et al., 2003). [Pg.75]

As regards tannin, the parts of the cortex, or true bark, in which it is mostly contained, are the exterior layers of the portion known as the liber, and the interior of the cortical tissue—the inside portions of the former, and the most exterior of the latter, yielding very little of this principlo. The same observation is true of other matters, such as quinine and the like. The various dyCB are seated frequently in the exterior portion of the cortical tissue. The sap always ascends through the cellulose of the real hark and as this fluid is the source from which tannin is socreted, it is evident that thcrO will be more of it in the bark, when the flow is greater than at other periods. Experiments have proved this to bo the caso as regards oak, and the same observation applies to the barks of other trees, such as the willow, elm, pine, birch, bcecli, et cetera, with equal force.. ... [Pg.505]

The fibrous tissue in the cell walls of plants contains the polysaccharide cellulose, which consists of long chains of glucose units, each of which is connected by a /3-glucoside link to the C4 hydroxyl of another glucose as in the... [Pg.932]

The network structure of lignin, which is made of phenol units, coagulates the cell wall in wood tissue, which is composed of cellulose and hemicellulose. Lignin is currently a waste product because of its complicated structure [1-4], It is produced by an oxidative polymerization of coniferyl alcohol, sinapil alcohol, and cumarol alcohol (Figure 1) catalyzed by metalloenzymes such as laccase and peroxidases. Laccase is a protein whose active center contains four coppers per one subunit [5-20],... [Pg.536]


See other pages where Tissues, cellulose-containing is mentioned: [Pg.23]    [Pg.57]    [Pg.149]    [Pg.150]    [Pg.430]    [Pg.527]    [Pg.372]    [Pg.145]    [Pg.239]    [Pg.213]    [Pg.39]    [Pg.60]    [Pg.577]    [Pg.24]    [Pg.432]    [Pg.52]    [Pg.20]    [Pg.355]    [Pg.190]    [Pg.62]    [Pg.103]    [Pg.107]    [Pg.333]    [Pg.33]    [Pg.181]    [Pg.108]    [Pg.675]    [Pg.360]    [Pg.8]    [Pg.268]    [Pg.318]    [Pg.15]    [Pg.161]    [Pg.340]    [Pg.84]    [Pg.355]    [Pg.376]    [Pg.107]    [Pg.463]    [Pg.47]    [Pg.411]   
See also in sourсe #XX -- [ Pg.150 ]




SEARCH



© 2024 chempedia.info