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'''Glycogenolysis''' is the chemical process by which [[glycogen]] is broken down into smaller molecules - normally [[glucose-6-phosphate]]. In the liver, the glucose-6-phosphate is further modified to glucose, and is released into the bloodstream. In muscle tissue, the glucose-6-phosphate is used as fuel by the muscle cell and is not released.
 
'''Glycogenolysis''' is the chemical process by which [[glycogen]] is broken down into smaller molecules - normally [[glucose-6-phosphate]]. In the liver, the glucose-6-phosphate is further modified to glucose, and is released into the bloodstream. In muscle tissue, the glucose-6-phosphate is used as fuel by the muscle cell and is not released.
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Glycogen is a complex polymer with a 'trunk' and 'branches'. Addition and removal of glucose subunits occurs only at the tips of the 'branches', not at the 'trunk'.
    
Glycogenolysis has two main steps; the first step, in which a glucose molecule is removed from the glycogen molecule as a [[glucose-1-phosphate]] molecule, and a second step in which the glucose-1-phosphate is converted to glucose-6-phosphate.  
 
Glycogenolysis has two main steps; the first step, in which a glucose molecule is removed from the glycogen molecule as a [[glucose-1-phosphate]] molecule, and a second step in which the glucose-1-phosphate is converted to glucose-6-phosphate.  
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Glycogen is a branched molecule, and the enzyme that clips a glucose-1-phosphate off the end of a branch, [[glycogen phosphorylase]], stops working when it is less than 5 glucose subunits of a branching point. A second set of two molecules, the [[debranching enzyme]], is then required to remove the branching point so that glycogen phosphorylase can continue working.
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The enzyme that clips a glucose-1-phosphate off the tip of a branch, [[glycogen phosphorylase]], stops working when it is less than 5 glucose subunits from a branching point. A second set of two molecules, the [[debranching enzymes]], are then required to remove the branching point so that glycogen phosphorylase can continue working.
    
Glycogenolysis is stimulated by the [[endocrine]] [[hormones]] [[glucagon]] and/or [[epinepherine]].
 
Glycogenolysis is stimulated by the [[endocrine]] [[hormones]] [[glucagon]] and/or [[epinepherine]].
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