Final answer:
Adding one glucose to the glycogen chain requires a total of 1 ATP equivalent, as the activation of glucose to UDP-glucose consumes 1 UTP, which is equivalent to 1 ATP.
Step-by-step explanation:
The process of adding glucose to the nonreducing end of glycogen for storage is an energy-consuming process. It requires the use of high-energy molecules such as ATP. Specifically, the activation of glucose to form UDP-glucose requires the hydrolysis of one UTP (which is energetically equivalent to ATP) to UDP plus inorganic phosphate. This activated form of glucose then adds to the nonreducing end of the glycogen chain. To summarize:
- Conversion of glucose-1-phosphate to UDP-glucose = 1 UTP (equivalent to 1 ATP)
- Transfer of glucose from UDP-glucose to glycogen = 0 ATP directly, but indirectly accounts for the original ATP spent to activate the glucose
Therefore, the total amount of ATP equivalents required to add one glucose molecule to glycogen is 1 ATP.