31. Which of the following is not directly required for chain elongation during translation?
(A) Ef-Tu
(B) A site on the ribosome
(C) GTP
(D) IF2

27. CDKs associate with cyclins at specific stages of the cell cycle. The CDK subunit is responsible for phosphorylating a substrate protein, while the cyclin is responsible for _____(A) degradation of the CDK after phosphorylation. (B) ubiquitin function. (C) determining which specific proteins will be phosphorylated. (D) dephosphorylating Rb.

28. Normal alleles of tumor suppressor genes function to encode proteins that (A) promote transition from G1-to-S. (B) can slow the rate of cell division. (C) increase the rate of mutagenesis. (D) activate oncogenes.

29. The sigma factor that mediates a global heat shock response in E. coli is (A) sigma 70. (B) sigma 32. (C) sigma 34. (D) sigma 72.

30. The critical step in the regulation of most bacterial genes occurs 參考用(A) during transcription. (B) at release of mRNA. (C) during translation. (D) post-translationally.

32. Amino acids differ from one another by the _____ that are present. (A) Amino group (B) R group (C) Core group (D) Carboxyl group

33. Which of these processes are coupled (linked) in prokaryotes but NOT in eukaryotes? (A) transcription and translation (B) replication and transcription (C) replication and translation (D) replication, transcription, and translation are not separate in prokaryotes

34. RNA molecules that can act as enzymes and catalyze specific biochemical reactions are known as (A) donors (B) splice acceptors (C) ribozymes (D) tRNAS

35. Which of the following is a form of RNA editing? 1. The polyadenylation of the pre-mRNA sequence. 2. The changing of the structures of individual bases 3. The insertion or deletion of uridine monophosphate residues (A) 1 (B) 3 (C) 1 and 3 (D) 2 and 3

36. Translation takes place at which part of the cell? (A) Nucleus (B) Mitochondria (C) Ribosome (D) Cytosol

37. The isolation of conditional cell cycle mutations in yeast helped identify many of the key proteins involved in cell cycle control. Many of these mutations were given the name cdc (cell division cycle) and are temperature sensitive. A cdc temperature sensitive mutant will: (A) grow normally at the permissive temperature and arrest at a specific phase in the cell cycle at non-permissive temperature.  (B) grow normally at non-permissive temperature and arrest at a specific phase in the cell cycle at permissive temperatures.  (C) grow slower at permissive temperature and speed up through the cell cycle at non-permissive temperatures. (D) grow normally at permissive temperature and have an extended period of time in G1 of the cell cycle at non-permissive temperatures.