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Carbohydrates are organic molecules that are used as energy sources. They are made by the chlorophyll in plants and trap solar energy in the form of water and carbon dioxide.
In animals, they are stored in the liver and other body tissues in the form of glycogen. Glycogen is a polysaccharide and it is formed from glucose.
1. It Is A Polysaccharide
The molecule is a long chain of monosaccharides linked together by glycosidic bonds. These polysaccharides can have a branched or unbranched structure and may contain different types of monosaccharides.
The main difference between starch and glycogen is that starch has only a-1-4 bonds while glycogen contains both a-1-4 and a-1-6 bonds. This makes it a very branched polysaccharide.
A branch point is created every 10 glucose units in the glycogen molecule, while it happens about every 24 to 30 in amylopectin. This means that amylopectin is a much more compact and crystalline polysaccharide than glycogen.
Glycogen is a branched polysaccharide of glucose molecules that is found in the liver and muscles of animals. It is the reserve form of glucose that is stored in these tissues when blood glucose levels are low. The hormone glucagon stimulates the breakdown of this sugar in these tissues, releasing glucose to be used as energy. This process is known as glycogenolysis.
2. It Is A Polymer
Carbohydrates are a class of biological molecules that contain carbon, hydrogen and oxygen in the same proportion found in water (C(H)2).
These atoms can be arranged in a variety of ways to produce different types of complex carbohydrates. The most common are polysaccharides, which are large molecules made of several repeating subunits, or monomers, called sugars.
Glucose is one of the most important carbohydrate monomers. It is a complex carbohydrate that can be used as a source of energy in the body or stored in the form of glycogen for later use.
Glycogen is a branched polymer of glucose that is produced and stored mainly in the liver and muscle cells. It is similar to amylopectin in structure but has more extensive branching at every 8 to 12 glucose units.
3. It Is A Polymer Of Glucose
The monosaccharides glucose and amylopectin are the main components of starch. The two strands of the chains of these sugars are linked by glycosidic bonds.
Glucose is the most common monosaccharide in nature and occurs in both linear and ring form (Figure 3). In aqueous solution, glucose is usually found in the ring form where the hydroxyl group below carbon number 1 is oriented alpha-direction (a) or beta-direction (b), depending on its acetal arrangement.
Glycogen is a polymer of glucose that stores energy. It is hydrated with water and forms granules inside different cells.
It is the primary short-term energy reserve in both plants and animals. It is biosynthesized by the liver and muscle cells and is transported to other tissues in need of energy.
4. It Is A Polymer Of Amylopectin
Glycogen is a less branched, but more compact, analogue of starch. This polymer of glucose residues linked by a-1,4 and a-(1,6) glycosidic bonds is found in the form of granules in the cytosol in many cell types and plays an important role in the glucose cycle.
It also forms an energy reserve that can be easily mobilized to meet a sudden need for glucose. Although cells throughout the body store some amount of glycogen, the liver stores the largest volume.
Amylopectin is a highly branched polysaccharide that differs from amylose by containing some of the alpha-1,6-glycosidic bond. This results in branch points occurring about every 25-30 sugars (see Fig. 18).
This helical structure allows amylopectin to be hydrolyzed more readily, be more soluble, and have lower density than amylose. Consequently, it is the most common type of starch in plants and the primary carbohydrate source in monogastric animals. In addition, it is a major part of the final configuration of starch and accounts for 70% to 80% of its mass.