Part 5基因组科与技术东南大学.doc

东 南 大 学 考 试 卷 答 题 纸 课程名称 基因组科学与技术 考试学期 得分 适用专业 生物医学工程 考试形式 开卷 考试时间长度 90分钟 共 6页 Part v How genes are regulated (chapter 16-19) 1. Transcription in prokaryotes and eukaryotes is similar in that: A) Transcriptional machinery controls compaction and decompaction of chromatin. B). The mRNA produced can undergo alternative splicing. C). Both prokaryotic and eukaryotic proteins have identical affinities for DNA. D). Both are contained within the cell nucleus. E). Both are regulated by attachment of proteins to DNA adjacent to the gene being transcribed. 2. How do negative regulators such as the lac repressor prevent RNA polymerase from initiating transcription? A) By blocking passage of the polymerase through the operator. B) By forming a loop in the operator that restricts the passage of the polymerase. C) By physically blocking the DNA binding site of RNA polymerase. D) By binding to the polymerase thus preventing its binding. 3. The __________________________ is the cis-acting DNA sequence that serves as the binding site for RNA polymerase. a. promoter b. terminator c. enhancer d. regulator e. initiator 4. Which statement is true regarding global gene regulation in bacteria? A) Sigma factors are not involved in gene regulation, just attachment of the polymerase to the promoter. B) Alternative sigma factors recognizing different promoters carry out global gene regulation. C) E. coli cells devote more energy to the production of ribosomes during stress so that global gene regulation can occur. D) All promoters are recognized by all sigma factors. 5. Why is glucose involved in the catabolite repression of the lactose operon? A) It has nothing to do with regulation of the lactose operon. B) It is produced by the enzymatic breakdown of lactose, its presence thereby signifying the presence of lactose in the cell. C) It is also a substrate for β-galactosidase. D) Its presence in the cell increases the amount of lac represor in the cell. 6. How