Part II – Glucose Utilization in Skeletal Muscle Cells
Questions
5. In an actively contracting skeletal muscle cell, what would cause a decrease in the rate of glucose diffusion into the cell?
6. In order to produce lactate from pyruvate, what items or inputs are required?
7. During glycolysis one molecule of glucose, which has six carbons, is split into two molecules of pyruvate, which
have three carbons each (Figure 4). Each pyruvate molecule can then be converted into a molecule of lactate,
which also has three carbons. Oxygen is not required for any of these processes to occur. Why?
8. After lactate is produced in the sarcoplasm, where might it go and how might it be used?
9. How does the production of lactate protect or buffer the cell from acidosis, which is defined as the accumulation
of H+ in a fluid filled compartment?
10. Look at the structure of lactate (Figure 4). Do you think it can leave the cell via simple diffusion? Why or why not?
