Final Exam - UNE Medical Biochemistry 1005 Questions With 100% Correct Answers

Final Exam - UNE Medical Biochemistry 1005 Questions With 100% Correct Answers What are the direct products of B-Oxidation? - answer1) NADH, FADH2 used in ETC --> ATP 2) Acetyl-CoA i) substrate for ketogenesis ii) Allosterically activates pyruvate carboxylase --> gluconeogenesis 3) ATP used in anabolic process in fasted state i) Gluconeogenesis ii) Urea Cycle An 11-year-old girl is brought to the emergency department by her father. He reports she has recently been very thirsty and needing to make frequent trips to the bathroom. At her soccer game today, she complained of lightheadedness and that the symptoms did not resolve even after drinking a power beverage. A rapid dipstick test revealed glucose in her urine and further diagnostics are consistent with a diagnosis of type 1 diabetes. Evaluation of this girl's liver would reveal an increased rate of which of the following processes? a) Fatty acid synthesis b) Glycogenesis c) Glycolysis d) Ketogenesis e) Protein Synthesis - answerKetogenesis 1) Type 1 Diabetes: loss of insulin production Increased Glucagon 2) Fed state (a) Fatty acid synthesis, glycogenesis, glycolysis 3) Fasted state (a) B-oxidation - increase Acetyl-CoA for ketone synthesis & Lipolyis increases free fatty acids for oxidation --> increase Acetyl-CoA What is the role of Adipose Tissue in metabolism? - answerStores Triacylglycerols (TAGs) --> broken down into fatty acids during fasted state to use as energy A 5-year-old female is brought to the emergency department by her mother. She is a type I diabetic and has not taken her insulin while away at a day camp. The child is unresponsive. Which of the following enzymes is phosphorylated and active under these conditions? a) Acetyl-CoA Carboxylase b) Hormone-sensitive Lipase c) Glycogen Synthase d) Phosphofructokinase 2 e) Pyruvate Kinase - answerb) Hormone-sensitive Lipase 1) Fed state (i) Acetyl-CoA Carboxylase - fatty acid synthesis (ii) Glycogen synthase - inactivated by phosphorylation; active in fed state (iii) PFK2 - inactivated by phosphorylation (iv) Pyruvate Kinase - inactivated by phosphorylation The process of ketogenesis refers to the conversion of acetyl-CoA to which of the following compounds? a) Methylmalonyl-CoA b) Malonyl-CoA c) B-Hydroxybutyrate d) Propionyl-CoA - answerc) B-Hydroxybutyrate What is the compound formed from the spontaneous decarboxylation of acetoacetate in the blood that is responsible for a fruity odor on the breath of someone with ketonemia? a) B-Hydroxybutyrate b) Acetyl-CoA c) Acetone d) Succinyl-CoA - answerc) Acetone A precipitating factor for the ketonemia associated with ketogenic diets, starvation, and untreated type 1 diabetes is: a) High-fat diet b) Defects in enzymes of B-oxidation c) Hyperglycemia d) Hypoinsulinemia - answerd) Hypoinsulinemia ATP can be generated by many metabolic pathways in the body. Which of the following processes generates the most ATP? a) Fatty acid oxidation b) Pentose Phosphate pathway c) TCA cycle d) Glycogenolysis e) Glycolysis - answera) Fatty acid oxidation Which of the following is the substrate for ketone synthesis? a) Glucagon b) Acetyl-CoA c) Glycerol d) Pyruvate - answerb) Acetyl-CoA Which of the following represents the correct sequence of events in a cycle of β-oxidation beginning with a saturated fatty acyl-CoA?