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Old 02-10-2012
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Biochemistry Seven Statements about Enzyme Inhibition!

Which of the following is not correct?
A) Statins are competitive inhibitors of HMG-CoA reductase.
B) Methotrexate is a competitive inhibitor of dihydrofolate reductase.
C) Ethanol has a lower Km for the enzyme lactate dehydrogenase compared with methanol.
D) Epinephrine inhibits insulin production in pancreatic β cells via α1 receptor-mediated inhibition of adenylyl cyclase.
E) Glucagon receptor has characteristic 7-helix membrane-spanning domains which is a G protein-coupled receptor.
F) Activation of α2 receptor by epinephrine eventually causes inhibition of protein kinase A.
G) Epinephrine α1 receptor acts via PIP2 system.
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Old 02-11-2012
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not sure guess....C
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Old 02-11-2012
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Ans E .....Glucagon receptor has characteristic 7-helix membrane-spanning domains which is a G protein-coupled receptor ........

I dont think ethanol is the substrate for LDH ......
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Old 02-11-2012
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I go for D... Ethanol does has a lower Km = higher affinity
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Old 02-11-2012
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i think its D.
alpha1 activation does not decrease insulin secretion, alpha2 does. (alpha1 decreases renin secretion).
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