UNE CHEM 1005 Midterm Study Guide Questions & Answers 100% Correct!

What enzyme is used by the gluconeogenic pathway but NOT in the glycolytic pathway? - ANSWERSPhosphoenolpyruvate Carboxykinase PEPCK Newborn screening results show a biotinidase deficiency in a 2 day old infant. The deficiency impairs the infant's ability to reuse and recycle biotin. Due to the enzymatic deficiency, the activity of what enzyme is likely impaired? - ANSWERSPyruvate carboxylase If unregulated, which of the following pairs of enzymes would represent a futile cycle? - ANSWERSFructose 1,6 -bisphosphate and phosphofructokinase-1 When cortisol binds to its receptor, which of the following events occur top stimulate gluconeogenesis? - ANSWERSEnhanced transcription of regulatory enzymes What compound allosterically activates pyruvate carboxylase - ANSWERSAcetyl-CoA When the insulin to glucagon ratio is low, glycogenolysis is activated in the liver. Which of the following is primary fate of the glucose 6-phosphate released under these conditions? - ANSWERSDephosphorylated and released into the blood to maintain blood glucose What are the two major contributors to maintaining blood glucose levels during fasting? - ANSWERSHepatic glycogenolysis and gluconeogenesis Pyruvate dehydrogenase complex is highly regulated. The enzyme that will be most active when which of the following compounds is high? - ANSWERSPyruvate A deficiency in thiamine can reduce the activity of the pyruvate dehydrogenase complex. Under these conditions, you would expect a higher than normal blood concentration of which of the following metabolites? - ANSWERSPyruvate A-ketoglutarate dehydrogenase is the enzyme responsible for one of the irreversible reactions in the TCA cycle, What conversion does it catalyze? - ANSWERSA-ketoglutarate to succinyl-CoA A 10-year old girl is swimming in a local competition. The intense exercise will increase intracellular calcium levels which in turn will increase flux thru the TCA cycle by stimulating the activity of all of the following enzymes EXCEPT - ANSWERSSuccinate Thiokinase TCA Cycle intermediates are always being removed for various reasons but the cycle does not run out of intermediates and stop. This is because the TCA cycle can replenish intermediates thru - ANSWERSUsing anaplerotic reactions A 1