Carbohydrates glycogen

The bottom line for any of the above disorders is that insulin action is lost. Insulin is the primary hormone that regulates the metabolism of glucose in its conversion to the storage of carbohydrate—glycogen stored in the liver and muscles. Insulin also... 

The complex carbohydrate glycogen, a polymer made of glucose monomer units, is found in animal tissue. 

A. After a meal of carbohydrates, glycogen is stored in the liver and in muscle, and triacyl-glycerols are stored in adipose tissue. The level of glucagon in the blood decreases, and gluconeogenesis decreases. The brain oxidizes glucose to C02 and EL20 while the red blood cells produce lactate. 

There is, however, a macromolecule with a function that can be expressed very precisely, that is built from a vast number of copies of a single kind of building block, and that needs to satisfy functional constraints that can be defined precisely. It is possible, therefore, to assess the extent to which the structure that exists in nature is optimal. This is the storage carbohydrate glycogen, and Melendez-Hevia has studied its structure very carefully from the point of view of optimization. 

Fig. 6.1 Structure of glycogen. The diagram illustrates the structure of the storage carbohydrate glycogen established by William Whelan and colleagues. It is not the same as the (wrong) structure illustrated in most biochemistry textbooks. There are three kinds of chains of glucose units labeled A, B, and C, together with a small protein called glycogenin at the center (labeled G). A-chains are linear, but B and C-chains are branched. There is only one C-chain, which differs from the B-chains by being connected to the central glycogenin...

The metabolic oxidation energy or calorific value of carbohydrates (glycogen) is around 17 kJ g , compared to about 39 kJ g for fats... 

If the intake of metabolic fuels is lower than is required for energy expenditure, the body s reserves of fat, carbohydrate (glycogen) and protein are used to meet energy needs. Especially in lean people, who have relatively small reserves of body fat, there is a relatively large loss of tissue protein when food intake is inadequate. As the deficiency continues, so there is an increasingly serious loss of tissue, until eventually essential tissue proteins are catabolized as metabolic fuels — a process that obviously cannot continue for long. 

Fig. 2.4 Hormone reaction cascade triggered by the arrival of the hormone molecule adrenalin (1) at a transmembrane receptor (2) on the surface of a liver cell. The receptor activates the membrane-anchored stimulatory G-protein (Gs) which carries the message to the effector, adenylate cyclase. This enzyme converts ATP to the most widespread second messenger molecule, cyclic adenosin monophosphate (cAMP). cAMP diffuses through the cell and triggers an enzyme cascade which ultimately leads to the degradation of the storage carbohydrate glycogen and the release of glucose from the cell.

In contrast to this strain, nitrogen starved non-heterocystous filamentous blue-green alga, Oscillatoria sp Miami BG 7 simultaneously and stoichiometrically photoproduce and CO in a ratio of 2 and both were accumulated in the gas phase. Preceeding the H2 and CO2 photoevolution step, the cells were needed to accumulate very high level of cellular carbohydrate (Glycogen) by photosynthesis. (Kumazawa, Mitsui 1981 Mitsui et al 1983). 

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