113年 - 113 國立成功大學_碩士班招生考試_口腔醫學研究所：生物化學#126002

1. The isoelectric point of a protein is (A) pH value where positive and negative charges are equal (B) Sedimentation constant of protein (C) Protein position in gel (D) The point of maximum protein binding to the uncharged surface (E) None of the above

2. There are five types of histones. The histones that stabilize DNA binding between nucleosomes are (A) H1 (B) H2A (C) H2B (D) H3 (E) H4

3. Which of the following is not a part of the cell plasma membrane? (A) Cholesterol (B) Phospholipids (C) Fatty acids (D) Glycoprotein (E) None of the above

4. Generally, the functions of vitamins in the body are as follows: (A) Catalyst (B) Enzymes (C) Activating factor (D) Coenzymes (E) All of the above

5. Many drugs work by inhibiting the activity of specific enzymes. The type of inhibition is usually (A) Allosteric (B) competitive (C) noncompetitive (D) Uncompetitive (E) participating in a chemical reaction

6. The pentose phosphate pathway produces a product used in the synthesis of nucleotides, DNA, and RNA. (A) Arginine (B) Glucose-1-phosphate (C) Glucose-6-phosphate (D) Glucose-5-phosphate (E) Phosphoribosylpyrophosphate

7. Proteins embedded in the outer phospholipid layer of low-density lipid (LDL) particles are (A) Interleukin-2 (B) Apolipoprotein C-25 (ApoС-25) (C) Apolipoprotein B-100 (ApoВ-100) (D) Fibroblast growth factor-23 (E) None of the above

8. Saturated fatty acids exist in a straight chain form. However, which of the following changes can make the saturated fatty acid chain bend: (A) Carboxyl carbon forms salt (B) Carboxyl carbon forms ester. (C) An oxygen atom is attached to two adjacent carbon atoms (D) A double bond is inserted between two adjacent carbon atoms (E) None of the above

9. Phosphoglyceride can be broken down by which of the following enzymes? (A) Phospholipase D (B) Phospholipase A1 (C) Phospholipase A2 (D) Phospholipase C (E) All of the above

10. High-density lipoprotein (HDL) has (A) More cholesterol than low-density lipoprotein (LDL) (B) Protein content lower than LDL (C) Higher protein content than LDL (D) Phospholipid content is higher than LDL (E) None of the above

11. Base pairing is a characteristic of RNA and DNA (A) Base pairs are held together by ionic bonds (B) Pairing of adenine and uracil in DNA (C) Pairing of adenine and thymine in RNA (D) Base pairs are held together by hydrogen bonds (E) None of the above

12. The complementary strand corresponding to polynucleotide 5' ATGCTACGC 3' is (A) 5' ATGCTACGC 3' (B) 5' TACGATGCG 3' (C) 5' GCGTAGCAT 3' (D) 5' CGCATCGTA 3' (E) None of the above

13. Ultraviolet rays can cause DNA distortion, resulting in the formation of (A) Uracil dimer (B) Thymine dimer (C) Cytosine dimer (D) Adenine dimer (E) guanine dimer

14. The formation of complementary DNA (cDNA) from genes in eukaryotic cells involves (A) Removing introns from RNA (B) Splicing of exons of RNA to form mRNA (C) Transcribe genes into corresponding RNA (D) The role of reverse transcriptase (E) All of the above

15. How does messenger RNA (mRNA) transfer to the cytoplasm for protein synthesis after being synthesized in the nucleus? (A) Move through nuclear pores (B) By binding to Hsp90 protein (C) First combine with microsomes (D) By attachment to the nuclear matrix (E) None of the above

16. Many steroid receptors have two zinc fingers involved in specific binding to DNA. Which amino acids can zinc coordinate with in these zinc finger structures? (A) Lysine and glycine (B) Cysteine and histidine (C) proline and alanine (D) Tryptophan and histidine (E) None of the above

17. The final product of glucose metabolism is (A) sucrose (B)UTP (C) ATP (D) GTP (E) ceramide

18. The electron transport chain in the inner mitochondrial membrane involves many reactions that lead to the formation of ATP. One of the ingredients involved is (A) Adrenochrome (B) Hypoxanthine (C) flavin adenine dinucleotide (D) Glycated insulin (E) None of the above

19. Which of the following statements about the melting temperature (tm) of DNA is correct? (A) The higher the content of G=C base pairs, the higher the tm (B) The higher the content of G=C base pairs, the lower the tm (C) The higher the A=T base pair content, the higher the tm (D) The higher the A=T base pair content, the lower the tm (E) None of the above

20. Which of the following enzymes is used in polymerase chain reaction (PCR)? (A) EcoRII (B) EcoRI (C) Taq DNA polymerase (D) RNA polymerase (E) DNA topoisomerase

21. In cell signaling, which of the following enzymes catalyzes phosphatidylinositol biphosphate (PIP2) to produce inositol triphosphate (IP3) and diacylglycerol? (A) Phosphodiesterase C (Phosphodiesterase C) (B) Phospholipase C (C) Phosphokinase C (D) Phospholipase A2 (E) Lipokinase

22. Which of the following enzymes directly phosphorylates tyrosines of membrane proteins to initiate cell signaling cascades? (A) Receptor guanylyl cyclases (B) Receptor threonine kinase (C) Receptor serine kinase (D) Receptor tyrosine kinase (E) Receptor tyrosine phosphatase

23. Which of the following is the smallest structural unit of a chromosome? (A) 30nm fiber (B) Nucleosome (C) Euchromatin (eurochromatin)' (D) Heterochromatin (E) None of the above

24. Which of the following enzymes are required for cellular DNA replication? (A) DNA helicase (B) DNA topoisomerase (C) DNA polymerase (D) RNA primase (E) All of the above

25. What effect do competitive inhibitors of enzymes have on enzyme-mediated reactions? (A) Vmax decreases and Km remains unchanged (B) Vmax increases, Km remains unchanged (C) Vmax remains unchanged and Km decreases (D) Vmax remains unchanged and Km increases (E) Vmax remains unchanged and Km remains unchanged