5. The ion channel that opens in response to acetylcholine is an example of a _________signal transduction system.
(A) G protein
(B) ligand-gated
(C) receptor-enzyme
(D) serpentine receptor
(E) voltage-gated

1. Post-translational modifications are essential for protein functions. Which of the following post-translational modifications will not occur to lysine? (A) Acetylation (B) Phosphorylation (C) Ubiquitination (D) Methylation (E) Glycation

2. FLAG-tag is often introduced to a protein for Western blotting, immunoprecipitation, or recombinant protein purification. It consists of an amino acid sequence DYKDDDDK. When a FLAG-tag is introduced a recombinant protein, how would it affect the net charge of the recombinant protein when buffered at neutral pH? (A)+4 (B)+1 (C)-2 (D)-3 (E)-5

3. Which of the following amino acids contains a β-branched side chain? (A) Alanine (B) Glutamate (C) Isoleucine (D) Proline(E) Tryptophan

4. Which statement is true regarding solutes that are soluble in water? (A) The solute must be ionic. (B) The water-solute interactions must be more energetically favorable than water-water interactions. (C) The solute must be nonpolar. (D) The undissolved solute particles must only be attracted to each other by van der Waals interactions. (E) The solute must be hydrophilic.

6.All of the following statements are true about free fatty acids released from adipose tissue expect(A) Fatty acids are hydrophobic.(B) Fatty acids are not soluble in blood, the cytosol, or any other water solution.(C) Fatty acids are transported in the blood by albumin.(D) Fatty acids bind to a hydrophilic binding pocket of albumin.(E) The released fatty acid is taken up by muscle and liver.

7. The synthesis of both glycerophospholipids and triacylglycerols involves (A) serine. (B) phosphatidylethanolamine. (C) phosphatidic acid. (D) phosphocholine. (E) phosphatidic acid phosphatase.

8. In the normal oxidation of an odd chain fatty acid, all of the following would be part of the process except (A) Each odd chain fatty acyl CoA will produce one propionyl-CoA. (B) Propionyl-CoA enters the mitochondria using the carnitine-palmitoy1transferase I system. (C) Propiony1-CoA is converted to methylmalonyl-CoA. (D) Methylmalony1-CoA is converted to succiny1-CoA. (E) The oxidation of an odd chain fatty acid requires biotin to produce propiony1-CoA.

9. Which of the following is not true regarding ketone bodies? (A) Ketone bodies form during the catabolism of fats. (B) Ketone bodies are an effective means for weight loss, since the body will excrete them in the urine. (C) The first enzyme used in the production of ketone bodies is thiolase. (D) Ketone bodies are usually an alternative fuel in all tissues. (E) None of the above

10. Regarding the mechanism for the control of the adenylate cyclase, which statement is incorrect? (A) It is a membrane protein. (B) It catalyzes the formation of cAMP using UTP. (C) It is often activated or inhibited by G proteins. (D) Its catalytic product is a second messenger in eukaryotic signal transduction. (E) Adrenaline activates the adenylate cyclase indirectly.

11. Which statement is correct? (A) The biosynthesis of dNTPs uses NTPs as the source. (B) The overall scheme of pyrimidine biosynthesis is the same as purine. (C) The pyrimidine catabolism is first degraded to the nucleobase. (D) The pyrimidine ring is assembled before it is attached to ribose-5-phosphate. (E) Ribonucleotide reductase catalyzes deoxyribose to ribose in all biology.