1. There are two advantages to having large storage molecules: space and osmolarity.
a. How many ATP molecules are needed if a liver cell stores the energy from 1,000
      glucose molecules as ATP? Assume the maximal yield of 32 ATP per glucose.
b. How is your answer related to space?
c. How is it related to osmolarity?

2. The intermediates in glycogen metabolism are phosphorylated molecules.
a. Locate the reducing and non-reducing ends of a glucose molecule. Which end is
      activated by being phosphorylated during glycogen synthesis?
b. What is the source of the first phosphate on glycogen synthesis intermediates?
c. Why isn't that considered part of the cost of glycogen synthesis?
d. What is the source of phosphate during glycogen degradation?
e. What is the energy cost of converting glycogen to glucose-6-P?

3. The molecules below are all intermediates in glycogen metabolism.
a. Identify each molecule.
b. Label each molecule with S if it is only involved in glycogen synthesis,
     D if it is only involved in glycogen degradation, and B if it occurs in both.
c. One molecule is only found in the active site of an enzyme.
      Underline the molecule and write the name of the enzyme below it.
d. Circle the molecule that is not part of glycogen degradation.
e. Write the molecules involved in glycogen synthesis in order.

4. The diagram below shows part of a glycogen molecule.
a. Locate the part of the molecule that is the substrate for glycogen synthase.
b. Locate a part of the molecule that is the substrate for the branching enzyme.
c. Draw the structure of the product of the branching enzyme.

5. The diagram below shows part of a glycogen molecule.
a. Locate a part of the molecule that is the substrate for glycogen phosphorylase.
b. Locate a part of the molecule that is the substrate for the debranching enzyme.
c. Draw the structure of the product of the debranching enzyme.

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