Week 6 UNE Medical Biochemistry Review Exam Questions With 100% Correct Answers

Week 6 UNE Medical Biochemistry Review Exam Questions With 100% Correct Answers Glycogen is stored primarily in the: - answerliver and skeletal muscles Pathway for synthesis and degradation are identical. True or False - answerTrue Enzymes used for Glycogen synthesis - answerPhosphoglucomutase, UDPGlc pyrophosphorylase, and Glycogen synthase Glycogen synthesis - UDPGlc pyrophosphorylase: - answerGlucose 1-P + UTP → UDPGlc Glycogen synthesis - Phosphoglucomutase - answerGlucose 6-P is isomerized → Glucose 1-P Glycogen synthesis - Glycogen synthase - answeradds UDPGlc → terminal end of glycogen (1→4 linkage) Glycogen synthesis - Glycogenin primer is required with - answerGlycogen synthase Glycogen degradation enzymes - answerGlycogen phosphorylase, and Glucose 6- Phosphatase Which enzyme is required to de-phosphorylate glucose to be released from the liver - answerGlucose 6-Phosphatase Key difference in liver vs. muscle glycogenolysis - answerGlucose 6-Phosphatase: Glucose 6- P → Free Glucose Glucose 6-Phosphatase - answerGlucose 6-P → Free Glucose What enzyme is deficient in the following glycogen storage disease? • von Gierke's disease - answerGlucose 6-Phosphatase What gluconeogenic enzyme is absent in muscle, accounting for its inability to use glycogen as a source for blood glucose? - answerGlucose 6-Phosphatase In the liver glycogen synthesis and degradation are regulated through two main mechanisms: - answerGlucagon activation of GPCR and Epinephrine binds α-adrenergic Glucagon activation of GPCR Activation of Adenylate cyclase → - answerincreases cAMP Glucagon activation of GPCR cAMP activates Protein kinase A (PKA) → - answerphosphorylates phosphorylase kinase Glucagon activation of GPCR phosphorylated phosphorylase kinase → - answerphosphorylates glycogen phosphorylase→ glycogen degradation Glucagon activation of GPCR cAMP activates PKA → - answerphosphorylates glycogen synthase →inactivates Glucagon activation of GPCR - answerActivation of Adenylate cyclase, cAMP activates Protein kinase A (PKA), and cAMP activates PKA Epinephrine binds α-adrenergic - answerCleavage of PIP, IP3, DAG Epinephrine binds α-adrenergic Cleavage of PIP → - answerIP3 and DAG Epinephrine binds α-adrenergic IP3 → - answerstimulates Ca2+ release from ER Epinephrine binds α-adrenergic ▪ Ca2+ stimulates two responses - answerCa2+ calmodulin → activates phosphorylase kinase and calmodulin dependent kinase Epinephrine binds α-adrenergic Ca2+ calmodulin → activates phosphorylase kinase - answerphosphorylate glycogen phosphorylase → glycogen degradation Epinephrine binds α-adrenergic Ca2+ calmodulin dependent kinase → - answerphosphorylates glycogen synthase →inactivates Epinephrine binds α-adrenergic DAG → - answeractivates protein kinase C (PKC)