Glucose
The initial molecule that enters the cell and serves as the starting point for glycogen synthesis.
What is glucose (free glucose)?
The molecule formed from glucose-6-phosphate during glycogen synthesis
What is Glucose-1-phosphate?
The activated form of glucose that directly provides glucose units for glycogen synthesis?
What is UDP-Glucose?
An enzyme that is primarily responsible for building glycogen by adding glucose molecules to a growing glycogen chain.
Is the enzyme glycogen synthase responsible for synthesizing the glycogen?
Enzyme that creates branches during glycogen synthesis.
What does the branching enzyme do during glycogen synthesis?
Enzyme that is responsible for capturing glucose inside the muscle cell by adding a phosphate group to carbon 6.
What is enzyme hexokinase?
The enzyme that changes glucose-6-phosphate into glucose-1-phosphate
What is Phosphoglucomutase?
The molecule that combines with glucose-1-phosphate to produce UDP-glucose.
What is UTP (Uridine Triphosphate)?
The activated glucose molecule that serves as the substrate for glycogen synthase.
Is UDP-glucose the activated molecule?
Type of bond formed by the branching enzyme.
Is the α-1,6 glycosidic bond formed by the branching enzyme?
Glucose-6-phosphate must be converted to glucose-1-phosphate. The type of enzyme that catalyzes this isomerization reaction.
What is mutase (specifically phosphoglucomutase)?
Glucose-1-phosphate must first be converted into UDP-glucose before being added to glycogen.
Does glucose-1-phosphate lack the energy required to be added to glycogen?
The enzyme that catalyzes the formation of UDP-glucose from glucose-1-phosphate.
What is UDP-glucose pyrophosphorylas?
The type of glycosidic bond that glycogen synthase forms when elongating the glycogen chain.
Is the α-1,4-glycosidic bond the one formed by glycogen synthase?
The importance of adding branches to glycogen.
Do the branches in glycogen serve to make it more compact and allow for faster glucose storage and release?
Glucose-1-phosphate cannot bind directly to the growing glycogen chain. High-energy nucleotide is required to "activate" glucose at this stage.
What is UTP (Uridine Triphosphate)?
The molecule formed from glucose-1-phosphate before glycogen can be built.
What is UDP-glucose?
The molecule that acts as the direct substrate for glycogen synthase.
Does UDP-glucose act as the direct substrate?
Hormone that activates glycogen synthase after a carbohydrate-rich meal.
Does insulin activate glycogen synthase?
The branching enzyme acts during glycogen synthesis.
Does the branching enzyme act by transferring a portion of the chain to form a branch once glycogen synthase has formed a sufficiently long chain?
During glucose activation, a molecule of inorganic pyrophosphate (PPi) is released. The subsequent degradation of this pyrophosphate by the enzyme pyrophosphatase is crucial for the metabolic pathway.
Is the primary function of PPi hydrolysis to release energy that renders the glucose activation reaction irreversible, thereby driving the entire process?
The correct sequence of molecules involved in glucose activation during glycogen synthesis.
What does this sequence represent: Glucose-6-phosphate → Glucose-1-phosphate → UDP-glucose?
Glucose must be converted into UDP-glucose before it can be incorporated into glycogen.
Does glucose need to be activated to provide sufficient energy for glycogen synthesis?
Glycogen synthase cannot initiate the synthesis of a new glycogen molecule on its own.
Does glycogen synthase require a pre-existing glycogen primer provided by the protein glycogenin?
If glycogen lacked branches.
Would glycogen be less efficient at storing and releasing glucose if its structure lacked its multiple branches?