1. Hers disease results from an absence of liven glycogen phosphorylase and may result in serious illness while McArdle disease, which results from an absence of muscle glycogen phospohrylase is much less serious, simply causing difficulty when exercising.  Why is Hers disease so much more serious?  

2. Between your evening meal and breakfast, your blood glucose drops and your liver becomes a net producer rather than consumer of glucose.  What hormone is produced to make your liver a net producer of glucose?  How does this hormone regulate glycogen phosphorylase and glycogen synthetase?

3. After your evening meal, your blood glucose level rises and your liver (and muscle cells) becomes a net consumer of glucose. What hormone is produced to make your liver (or muscles) a net consumer of glucose? What hormone is produced to make your liver a net producer of glucose?  How does this hormone regulate glycogen phosphorylase and glycogen synthetase?

4. Mature erythrocytes, which lack mitochondria, metabolize glucose at a high rate.  In response to the increased availability of glucose, erythrocytes generate lactate and also evolve carbon dioxide.

a. Why is the generation of lactate necessary to ensure the continued utilization of glucose?

b. In erythrocytes, what pathway is likely to be used for the generation of carbon dioxide from glucose?  

5. Liver and other organ meats contain large quantities of nucleic acids.  In the course of digestion of these meats, RNA is hydrolyzed to ribose, among other chemicals.  Explain how ribose can be used as a fuel.

6. Why do deficiencies in glucose-6-phosphate dehydrogenase frequently present as anemia?