UNE Medical Biochemistry Unit 3 Review (For this guide, I made the questions from the video lectures, study guides, and quiz/test reviews) Rated A+

UNE Medical Biochemistry Unit 3 Review (For this guide, I made the questions from the video lectures, study guides, and quiz/test reviews) Rated A+ What occurs when glucagon is high and insulin is low? Beta-oxidation During the fasted state, the liver uses ______ as fuel and the pathway is _______. Fatty acids, Lipolysis in the adipose During the fasted state, the red blood cell uses ______ as fuel and the pathway is _______. Glucose, Hepatic glycogenolysis, and gluconeogenesis During the fasted state, the brain uses ______ as fuel and the pathway is _______. Glucose, Hepatic glycogenolysis, and gluconeogenesis During the fasted state, the skeletal muscle uses ______ as fuel and the pathway is _______. Fatty acids, Lipolysis in the adipose Process of generating acetyl-CoA, NADH and FADH2 from the oxidation of free fatty acids taken up by the peripheral tissues β - oxidation Process of releasing free fatty acids from triacylglycerols stored in the adipose in the fasted state Lipolysis Where does beta oxidation occur? mitochondria What enzyme is used to add acyl-CoA to free fatty acids which is able to travel across the outer mitochondrial membrane? Acyl-CoA synthetase Carnitine and Acyl-CoA use what enzyme to transfer the acyl group to carnitine to synthesize acylcarnitine? Carnitine palmitoyl transferase I Acylcarnitine is transported across the inner mitochondrial membrane via what enzyme? This enzyme can also recycle carnitine. Carnitine acylcarnitine translocase The two transporter enzymes needed to get free fatty acids from the cytosol to the mitochondria are? Carnitine palmitoyl transferase I and Carnitine palmitoyl transferase II What are the four steps of the full beta-oxidation spiral? Dehydrogenase - Hydrolase - Dehydrogenase - Thiolase What are the products of Beta-oxidation? Acetyl CoA, NADH, FADH2 What products of beta-oxidation will be oxidized in the electron transport chain to produce ATP? NADH and FADH2 What product from beta-oxidation will be used during ketogenesis? Acteyl-CoA What inhibits carnitine palmitoyl transferase I to ensure beta-oxidation is not occurring at the same time as fatty acid synthesis? Malonyl-CoA Elevated levels of what in the cytosol is an indication fatty acid synthesis is occurring? Malonyl-CoA ATP is required for what anabolic processes in the fasted state? Gluconeogenesis and the urea cycle What allosterically activates pyruvate carboxylase? Acetyl-CoA 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? Ketogenesis Process of generating ketones from excess acetyl-CoA produced from β - oxidation Ketogenesis As acetyl-CoA levels elevate in the mitochondria what enzyme will produce acetoacetyl-CoA? Thiolase What enzyme generates HMG-CoA from acetoacetyl-CoA? HMG-CoA synthase What cleaves HMG-CoA into acetoacetate? HMG-CoA lyase What are two things that can happen to acetoacetate? Reduced to D-3 hydroxybutyrate or spontaneously decarboxylate to acetone What are the two ketone bodies in ketogenesis? D-3 hydroxybutyrate and acetoacetate What cofactor is required for acetoacetate to become D-3 hydroxybutyrate? NADH The liver lacks what enzyme to use ketone bodies as a source of energy? Thiophorase In what ways is ketogenesis regulated? Activity of lipolysis Inhibition of CPT-I by Malonyl-CoA Flux through the TCA depending on NADH levels and concentration of intermediates, specifically oxaloacetate Ketoacidosis can occur from prolonged ketogenesis by? Starvation or uncontrolled diabetes During the fed state, glucose from the blood is phosphorylated into Glucose 6-Phosphate which undergoes esterification in the adipose tissue to what? Stored triacyclglycerols Triacylglycerol can come from glucose in the fed state but can also come from either dietary means transported by? Chylomicrons or fatty acid synthesis in the liver transported by VLDLs Chylomicrons or VLDLs interact with lipoprotein tissue to hydrolyze triacyclglycerols into? Free fatty acids and glycerol hormone sensitive lipase is activated by? glucagon and epinephrine What inhibits the hydrolysis of triacyclglycerols into free fatty acids and glycerol? Insulin What enzyme hydrolyzes triacyclglycerols into free fatty acids and glycerol? Hormone sensitive lipase Free fatty acids enter the bloodstream during lipolysis and are used as a source of energy for? Peripheral tissues Glycerol from lipolysis can go to the liver and be used as a substrate for what? Gluconeogenesis What activates adenyl cyclase? glucagon and epinephrine what inhibits adenyl cyclase? insulin What increases the levels of cAMP? adenyl cyclase What activates cAMP dependent protein kinase? cAMP Hormone sensitive lipase is phosphorylated and changed from inactive to active by what? cAMP dependent protein kinase If insulin levels are high, what enzyme is activated to deactivate and dephosphorylate hormone sensitive lipase? Lipase phosphatase What is the role of adipose in metabolism? Storage of triacyclglycerols but it also has many other roles. For this course, this is what matters. A 5-year-old female is brought to the emergency department by her mother. She is a type 1 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? Hormone sensitive lipase _____ provides free fatty acids for _____ Lipolysis, Beta-oxidation _____ generates NADH and FADH2 that is oxidized in the _____ to produce ATP Beta-oxidation, Electron transport chain _____ generates acetyl-CoA that is a substrate used in _____ Beta-oxidation, ketogenesis _____ reduces acetyl-CoA for the _____