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 35-year-old African American man presents with fever, abdominal pain, and severe weakness since yesterday. On physical examination, the patient is jaundiced and shows a generalized pallor. Past medical history is significant for recently receiving anti-malaria prophylaxis before visiting Nigeria. Laboratory tests show decreased glucose-6-phosphate dehydrogenase (G6PD) levels. Peripheral smear shows the presence of bite cells and Heinz bodies. Which of the following is the most likely diagnosis in this patient?
AAutoimmune hemolytic anemia
BSickle cell disease
CGlucose-6-phosphate-dehydrogenase (G6PD) deficiency
DMicroangiopathic hemolytic anemia
EParoxysmal nocturnal hemoglobinuria (PNH)
An 11-year-old boy is brought to the emergency room with acute abdominal pain and hematuria. Past medical history is significant for malaria. On physical examination, he has jaundice and a generalized pallor. His hemoglobin is 5 g/dL, and his peripheral blood smear reveals fragmented RBC, microspherocytes, and eccentrocytes (bite cells). Which of the following reactions catalyzed by the enzyme is most likely deficient in this patient?
AGlucose-1-phosphate + UTP → UDP-glucose + pyrophosphate
BGlucose + ATP → Glucose-6-phosphate + ADP + H+
CD-glucose 6-phosphate → D-fructose-6-phosphate
DGlucose-6-phosphate + H2O → glucose + Pi
ED-glucose-6-phosphate + NADP+ → 6-phospho-D-glucono-1,5-lactone + NADPH + H+
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