Polysaccharides
The Polysaccharides: Starch and Fiber
Starches and fibers are also called complex carbohydrates because they are made of long chains of glucose, as plants store glucose in the form of starch. Starch is a natural component of most plants, fruits, grains, and vegetables. Starch is also called polysaccharides, and each starch molecule is composed of numerous glucose units joined together. Most green plants produce this polysaccharide for energy storage.
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In human bodies, glycogen is the energy reserve; glycogen is a highly branched version of starch. Starch is a polysaccharide comprising glucose monomers joined together to form long-molecular chains.
Starch and Fibers
Starch and fibres are carbohydrates and polysaccharides; they have long chains composed of glucose molecule units.
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Starch and fibre often need clarification since both are contained in the same foods and with macromolecular structures. In starch, chains of glucose monomers (monomer means one single molecule) are joined by alpha bonds, which can be broken down in the small intestine. In fibre, glucose monomers are joined by beta bonds, which can not be broken down; instead, the chains remain intact throughout their passage through the small intestine.
Starch
starch like amylopectin, found in potato, rice, bread and pasta, wheat and barley) are made with alpha-glucose monomers. The bond angles are formed when alpha-glucose monomers join a branched or spiral structure. These bonds can be broken down by enzymes in the digestive system.
Fiber
Polysaccharides like cellulose in plants are made with beta-glucose monomers. The bond angles are formed when glucose units join and build into stable, strongly interlinked parallel chains. Enzymes in the small intestine can not break down these beta-bonds in fibres.