Crib death of infants when fasting (i.e., when sleeping and not eating – therefore a low blood glucose condition) is also known as sudden infant death syndrome (SIDS). SIDS was often blamed on lack of proper care by the parents of the child. It is now known that a significant number of SIDS cases are caused by a genetic defect in the gene that codes for fatty acyl-CoA dehydrogenase, the enzyme that catalyzes the first step in fatty acid β-oxidation (see question 34 for this reaction). If this enzyme is defective, energy from fatty acids is not available and, in addition, gluconeogenesis is inhibited resulting in severe and life-threatening hypoglycemia (low blood glucose). Why the hypoglycemia?

In a cell when oxygen (O2) is limited, NAD+  levels decrease inhibiting the activities of several enzymes including the PDH complex. What other enzymes would be inhitibed by low levels of NAD+?

In glycolysis, the reaction sequence between dihydroxyacetone phosphate and 2-phosphoglycerate involves all of the following EXCEPT:

Glucagon released during periods of low blood glucose among its other effects also activates the gene transcription for the gene that encodes phosphoenolpyruvate carboxykinase. The carbon flux through which pathway will be increased by increased levels of glucagon?

Avidin is a protein found in the eggs of birds that binds biotin with high affinity and is a strong inhibitor of biotin-requiring enzymes (recall that biotin is a necessary coenzyme for CO2 transfers). You perform an experiment using liver cells that are capable of gluconeogenesis growing in culture. You add each of the following (answers A, B, C, D, or E) as potential substrates (assume each is readily transported into the cell and/or mitochondria) and you measure the amount of glucose synthesized and record in your lab book that all these substrates will support glucose synthesis. For your test cultures, you add each of the substrates (answers A, B, C, D, or E) and include avidin in each culture. You measure the levels of glucose synthesized and record this in your lab book. Which substrate will NOT support synthesis of glucose in the presence of avidin?

What liver enzyme, based on its kinetic properties (i.e., not inhibited by its product and a high Km), has a controlling influence over blood glucose levels after eating a meal?

VI. C Administrative Functions (Cognitive) 10. List steps involved in completing an inventory   Question: Only qualified inventory specialist can place orders for a physician’s office. 

V.C Concepts of Effective Communication (Cognitive) 7. Recognize elements of fundamental writing skills   Question: Which is most likely not an element of good writing skills? 

VI. C Administrative Functions (Cognitive) 3. Identify critical information required for scheduling patient procedures   Question: What information would not be required when scheduling a patient for a procedure. 

For questions 44 – 46, you will be asked to identify the parts of the refracting telescope shown below.  Choose your answer based on the letters shown in the figure.