Principal structure components

In terms of function, polysaccharides fall into one of two groups structural and nutritional. For example, cellulose is a principal structural component of plants. Glycogen and starch, in contrast, are nutritional reservoirs for animals and plants, respectively. Monosaccharides may be mobilized from storage reservoirs such as glycogen and starch and then be metabolized to generate energy. 

Figure 1. The principal structural components of the growing cell walls of a Dicotyledon. The drawings are approximately to scale.

Cellulose is the principal structural component of vegetable matter. Wood is 30-40% cellulose, cotton over 90%. Photosynthesis in plants is responsible for the formation of 109 tons per year of cellulose. Structurally, cellulose is a polysaccharide composed of several thousand D-glucose units joined by (3(l,4)-glycosidic linkages (Figure 25.8). Complete hydrolysis of all the glycosidic bonds of cellulose yields D-glucose. The disaccharide fraction that results from partial hydrolysis is cellobiose. 

Fibrillin microfibrils are widely distributed extracellular matrix assemblies that endow elastic and non elastic connective tissues with long-range elasticity. They direct tropoelastin deposition during elastic fibrillogenesis and form an outer mantle for mature elastic fibers. Microfibril arrays are also abundant in dynamic tissues that do not express elastin, such as the ciliary zonules of the eye. Mutations in fibrillin-1—the principal structural component of microfibrils—cause Marfan syndrome, a heritable disease with severe aortic, ocular, and skeletal defects. Isolated fibrillin-rich microfibrils have a complex 56 nm beads-on-a-string appearance the molecular basis of their assembly and... 

Due to their simplicity of construction, ease of modification, electrical methods of detection, fast response time and the fact that they are the principal structural component of all biomembranes, conventional bilayer lipid membrane (BLM) arises as an ideal system for biosensor technology [88] and they have been studied regarding the possibility of developing DNA biosensors consisting of a glassy carbon electrode-modified by a BLM with incorporated ssDNA [89]. 

The plant cell wall is the principal structural component of the cell surrounding the protoplast and exterior to the plasmalemma. This structure is dynamic in that its shape, composition, and properties are constantly changing in response to growth, the stage of differentiation, the environment of the cell, and its activities. 

DOE Order 5480.23, Chg. I, Nuclear Safety Analysis Reports, Paragraph 8.b.(3)(d), as amplified in paragraph 4.f.(3)(d)4 of Attachment 1 to the Order, requires a description of the facility and operations conducted in the facility, including design of principal structures, components, systems, engineered safety features, and processes. (DOE 1994a). 

Floating offshore system (a variety of which is illustrated in Fig. 24.9) consists of three principal structural components ... 

Proteins are commonly classified into two main classes, viz fibrous and globular proteins. The former are the principal structural components of such materials as feathers, hair, nails and silk they consist of essentially linear polymers which are not dispersible in water. Globular proteins occur in materials such as egg-white, enzymes, metabolic intermediates and milk they are relatively compact cross-linked polymers and are dispersible in water. 

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