UNE Medical Biochemistry Unit 3 Midterm Test Exam With 100% Correct Answers

UNE Medical Biochemistry Unit 3 Midterm Test Exam With 100% Correct Answers In the fasted state, fatty acyl-CoA are transported across the mitochondrial membrane. The transport of fatty acids via carnitine palmitoyl transferase I (CPTI) can be directly inhibited by which of the following compounds? a. Malonyl CoA b. Carnitine c. Acetyl CoA d. Palmitate - answerMalonyl CoA Under fasting conditions (ratio of insulin to glucagon <1), elevated glucagon will activate which of the following enzymes? a. glycogen synthase b. lipoprotein lipase c. hormone sensitive lipase d. pyruvate dehydrogenase complex - answerhormone sensitive lipase ATP can be generated by many metabolic pathways in the body. Which of the following processes generates the most ATP? a. glycogenolysis b. fatty acid β-oxidation c. pentose phosphate pathway d. citric acid cycle - answerFatty acid β-oxidation In liver, which of the following key inhibitory events ensures that newly synthesized palmitoyl-CoA is not immediately oxidized? a. Inhibition of CPT-II by acetyl-CoA b. Inhibition of CPT-I by malonyl-CoA c. Inhibition of CPT-I by palmitoyl-carnitine d. Inhibition of acyl-CoA synthetase by malonyl-CoA - answerInhibition of CPT-I by malonyl-CoA Ketonuria, hyperglycemia and severe acidosis are prime diagnostic indicators of the presentation of Type I diabetic ketoacidosis. Which of the following compounds are "ketone bodies" that would be elevated in serum and urine of a patient in this condition? a. fumarate and succinate b. pyruvate and lactate c. acetone and ethanol d. D-3-hydroxybutyrate and acetoacetate e. oxaloacetate and pyruvate - answerD-3-hydroxybutyrate and acetoacetate Which of the following is NOT a product of β-oxidation? a. NADH b. FADH2 c. NADPH d. Acetyl-CoA - answerNADPH A well, 2-year-old girl presents to the clinic with symptoms of a viral illness. Her parents report she has had bouts of vomiting and diarrhea over the last 24 hours. This morning they could barely wake her from her crib and she was very weak. Laboratory tests show low blood glucose (hypoglycemia) and elevated liver enzymes. There are no ketones present in her urine. The child is hospitalized and glucose is administered by I.V. Additional laboratory tests showed elevated medium-chain fatty acyl carnitines in blood and 6-8 carbon dicarboxylic acids in the urine. Which of the following abnormalities is the most likely diagnosis for this child? - answerDefect of medium-chain coenzyme A dehydrogenase An individual is on a hunger strike and has not eaten in 13 days. Which of the following best describes their metabolic state? a. glycolysis will be highly active b. the brain will be preferentially oxidizing ketones c. glycogenolysis will be the primary source of blood glucose d. skeletal muscle will be primarily oxidizing glucose - answerthe brain will be preferentially oxidizing ketones (under conditions of starvation, the brain will begin to oxidize ketones as a primary fuel source reducing it's reliance on glucose) Insulin stimulates lipogenesis through several mechanisms. Which of the following is NOT an insulin stimulated process that enhances lipogenesis? a. decreased activity of the PDC b. increased glucose transport into the cells c. decreased levels of cAMP