Animals carbohydrate storage

A class of a-1,4 polymers of glucose used for carbohydrate storage in plants and animals, (p. 1137)... 

An extensively branched a-1,4 polymer of D-glucopyranose used for carbohydrate storage in animals. Branching occurs at a-1,6 glycosidic linkages. 

RufT degradation A method for shortening the chain of an aldose by one carbon atom by treatment with bromine water, followed by hydrogen peroxide and Fe2(S04)3. (p. 1120) starches A class of a-1,4 polymers of glucose used for carbohydrate storage in plants and animals, (p. 1135)... 

When corticosteroids are administered to animals starved for 48-72 hours, a paradoxical effect is observed. In spite of an increase in carbohydrate storage in the liver, muscle, and body fluid, the new glucose made available by the hormone is not used for oxidation. This observation suggests that corticoid hormones depress glucose utilization. Such findings are difficult to reconcile with the effects of cortisone and adrenalectomy on phosphorylase, phosphoglucomu-tase, and phosphohexose isomerase activity. The activities of these three enzymes are depressed by adrenalectomy, but are normalized by cortisone administration. 

Glycogen is the major form of carbohydrate storage in animals and is present in most animal cells. It may form up to 80 g/kg of fresh liver and up to 100 g/kg of fresh muscle. Most is present in the latter. The release of energy from glycogen necessitates... 

Polysaccharides, Polysaccharides are large sugar complexes that contain repeating sequences of simple sugars— chains of monosaccharides. In plants and animals they are used either for carbohydrate storage or structural support... 

It has been estimated that >90% of the carbohydrate mass in nature is in the form of polysaccharides. In living organisms, carbohydrates play important roles. In terms of mass, the greatest amounts by far are stmctural components and food reserve materials, in that order and both in plants. However, carbohydrate molecules also serve as stmctural and energy storage substances in animals and serve a variety of other essential roles in both plants and animals. 

Storage polysaccharides are an important carbohydrate form in plants and animals. It seems likely that organisms store carbohydrates in the form of polysaccharides rather than as monosaccharides to lower the osmotic pressure of the sugar reserves. Because osmotic pressures depend only on numbers of molecules, the osmotic pressure is greatly reduced by formation of a few polysaccharide molecules out of thousands (or even millions) of monosaccharide units. 

Glycogen is the major storage carbohydrate in animals, corresponding to starch in plants it is a branched polymer of a-D-glucose. It occurs mainly in liver (up to 6%) and muscle, where it rarely exceeds 1%. However, because of its greater mass, muscle contains about three to four times as much glycogen as does liver (Table 18—1). 

Carbohydrates Sugars, starch, cellulose Structural components of plant cells easily released energy storage in plants and animals Sugars in fruits starch and cellulose in plants glycogen in animals below 1... 

Classic beri-beri, rarely seen in the United States and Europe, except in alcoholism (P4), is endemic in the Far East because of the prevalent diet of decorticated rice (F6). It occurs in two forms wet beri-beri, characterized by edema and cardiovascular symptoms (G6), and dry beri-beri with peripheral neuritis, paralysis, and atrophy of the muscles. Conditions which may predispose to deficiency by increasing thiamine requirements are pregnancy (see section 2.4), and lactation, hyperthyroidism, malignant disease, febrile conditions, increased muscular activity, high carbohydrate diets, and parenteral administration of glucose solutions. A constant supply of thiamine is required for optimal nutrition because storage in the liver and elsewhere is limited. Thiamine is synthesized by bacteria in the intestinal tract of various animals, but this is not a dependable source for man. 

Triacylglycerol. Triglyceride a compound consisting of three molecules of fatty acids esterified to glycerol. It is a neutral fat synthesized from carbohydrates for storage in animal adipose cells. On enzymatic hydrolysis, it releases free fatty acids in the blood. Tuberculosis. Any of the infectious diseases of man and animals caused by species Mycobacterium and characterized by the formation of tubercles and caseous necrosis in the tissues. 

---