27. Which among the listed reactions is a part of the first step leading to the formation of heme? a. decarboxylation of Ser b. decarboxylation of Glu c. decarboxylation of Gly d. decarboxylation of His e. decarboxylation of ornithine 28. Neurotransmitter Serotonin is derived by: a. hydroxylation of Tyr b. decarboxylation of Glu c. hydroxylation and acetylation of Trp d. hydroxylation of Phe e. hydroxylation and decarboxylation of Trp 29. Which amino acid is the precursor of nitric oxide? a. Asp b. Arg c. Ala d. Citrulline e. Tyr 30. NO acts as a vasodilator by activating: a. adenylate cyclase b. Phe hydroxylase c. Tyr hydroxylase d. monoamine oxidase e. guanylate cyclase 31. The donor for the methyl residue of epinephrine is: a. 5-methyl-FH4 b. 10-formyl-FH4 c. S-Adenosylmethionine d. NADH e. coenzyme A 32. Coenzyme carrying one-carbon units is: a. Vitamin B12 b. Ascorbic acid c. Pyridoxal phosphate d. creatine e. Tetrahydrofolate 33. The aminotransferase reaction, in which an enzyme-PLP Schiff base forms, follows a(n) kinetic mechanism. A) sequential (single-displacement) ordered B) sequential (single-displacement) random C) Ping Pong (double-displacement) D) unknown 34. Ketogenic amino acids are broken down to acetoacetate or A) acetyl-CoA B) succinate C) citrate D) alpha-ketoglutarate E) pyruvate 35. The amino acids Ala, Cys, Gly, Ser, and Thr are all degraded to the metabolite A) acetyl-CoA B) succinate C) citrate
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The first step leading to the formation of heme involves the decarboxylation of Glycine (Gly). Therefore, the correct answer is c. decarboxylation of Gly. Show more…
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