A 45-year-old man is brought to the emergency department by ambulance after vomiting blood. The patient reports that he only ate a small snack the morning before and had not eaten anything for over 24 hours. At the hospital, the patient is stabilized. He is admitted to a surgical floor and placed on NPO with a nasogastric tube set to intermittent suction. He has been previously diagnosed with liver cirrhosis. An esophagogastroduodenoscopy (EGD) has been planned for the next afternoon. At the time of endoscopy, some pathways were generating glucose to maintain serum glucose levels. Which of the following enzymes catalyzes the irreversible biochemical reaction of this process?
AGlucose-6-phosphate dehydrogenase
BGlycogen phosphorylase
CEnolase
DGlyceraldehyde-3-phosphate dehydrogenase
EFructose-1,6-bisphosphatase
To prepare for an endoscopy, a 27-year-old male was asked by the gastroenterologist to fast overnight for his 12 p.m. appointment the next day. Therefore, his last meal was dinner at 5 p.m. the day before the appointment. By 12 p.m. the day of the appointment, his primary source of glucose was being generated from gluconeogenesis, which occurs via the reversal of glycolysis with extra enzymes to bypass the irreversible steps in glycolysis. Which of the following irreversible steps of gluconeogenesis occurs in the mitochondria?
AGlucose-6-phosphate to glucose
BPyruvate to oxaloacetate
CPhosphoenolypyruvate to pyruvate
DGlucose-6-phosphate to 6-phosphogluconolactone
EFructose-1,6-bisphosphate to fructose-6-phosphate
A 2-year-old boy presents to the emergency department with new onset seizures. After controlling the seizures with fosphenytoin loading, a history is obtained that reveals mild hypotonia and developmental delay since birth. There is also a history of a genetic biochemical disorder on the maternal side but the family does not know the name of the disease. Physical exam is unrevealing and initial lab testing shows a pH of 7.34 with a pCO2 of 31 (normal range 35-45) and a bicarbonate level of 17 mEq/L (normal range 22-28). Further bloodwork shows an accumulation of alanine and pyruvate. A deficiency in which of the following enzymes is most likely responsible for this patient's clinical syndrome?
AGlucose-6-phosphatase
BAlanine transaminase
CGlucose-6-phosphate dehydrogenase
DPyruvate dehydrogenase
EPyruvate kinase
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