QUESTION 42 Which of the following statements is INCORRECT? O a. In a protein kinase cascade, the signal is amplified at each step of the cascade. O b. The major difference between a cell that responds to a signal and one that does not is the presence of a receptor O c. Adenylyl cyclase is an enzyme that catalyzes the conversion of ATP to CAMP. O d. In a protein kinase cascade, variation in the response is not possible. O e. Signals can reach target cells in multicellular organisms by diffusion or by circulation in the blood.

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Question 12 Identify the key step in regulation of protein hormone release. O A. Exocytosis B. Signal sequence cleavage O C. Diffusion through the cell membrane D. Kinase activation of biosynthetic enzymes E. Golgi transport

Question one parts A though e a. You have a plan to make the cellular signaling peptide RGD (Arg-Gly-Asp). If you are beginning from the Arginine (Arg) amino acid, which amino acid(s) will require NH2 protection to optimize the synthesis? A) All 3 amino acids will need NH2 protection B) Gly and Asp will need NH2 protection C) Arg and Gly will need NH2 protection D) Only Arg b. Which of the following amino acids will not produce a purple color (indicative of 2 ninhydrin molecules binding) when reacted with ninhydrin? A) phenylalanine B) valine C) proline D) histidine c. If you had a mixture of leucine, arginine, and glutamic acid in a pH of 6 and applied a drop onto paper connected to an electrophoresis apparatus. Which of these would move toward the cathode (-). A) Leucine B) Arginine C) Glutamic Acid D) None of them d. True/False - Dicyclehexvlcarbodiimide is a typical reagent in peptide synthesis for protecting carboxylic acid groups. e. True/False t-butoxycarbonyl dicarbonate…