CHAPTER 18 REGULATION OF

Concept 18.1 Bacterial Regulation of 1. The basic concept of : a. Define

b. List all components and their functions included in an operon. i. ______

ii. ______

iii. ______

c. What is the function of an operon?

2. Use trp operon as an example to explain the concept of a repressive operon.

3. Use as an example to explain the concept of an inducible operaon.

4. List two types of negative gene regulation ______and ______; one type of positive gene regulation______. 5. Explain how cyclic AMP and catabolite activator are affected by glucose concentration.

Concept 18.2 Regulation of Eukaryotic Gene Expression 6. Define differential gene expression.

7. Concept check 18.2 Page 364 a. Explain how DNA methylation and histone acetylation affects chromatin structure and the regulation of transcription.

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b. Compare the roles of general and specific transcription factors.

c. Suppose you compared the nucleotide sequences of the distal control elements in the enhancers of three genes that are expressed only in muscle tissue. What would you expect to find and why?

8. Define epigenetic inheritance.

9. Describe the organization of a typical eukaryotic gene (from upstream to downstream) (Figure 18.8).

10. Explain the role of promoters, enhancers, activators, and repressors in transcriptional control. Function Control elements

Promoter

Enhancer

Activator

Repressor

Terminator

11. What makes liver cell and lens cell different?

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12. List the level of gene expression control in eukaryotes (page 378).

13. Describe factors that influence the lifespan of mRNA in the cytoplasm. Compare the longevity of mRNA in prokaryotes and eukaryotes.

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Concept 18.3 The Roles of Noncoding RNAs 14. Distinguish between small interfering RNAs (siRNAs) and miRNAs.

15. What are the roles of noncoding RNAs play in controlling gene expression?

Concept 18.4 Differentiation of gene expression 16. Name and define three interrelated processes that are responsible for embryonic development. Processes Definition Determination

Differentiation

Morphogenesis

17. Describe the two sources of information that instruct a cell to express genes at the appropriate time (Figure 18.17). 4

18. Describe the role of myoD in skeletal muscle development.

19. Define

20. Concept 18.4 page 373 a. Why the products of many mitotic divisions are not composed of identical cells?

b. What are the fruit fly maternal effect genes are also called egg-polarity genes?

21. Describe how gradients may specify the axes of developing Drosophila embryos.

Concept 18.5 Molecular Biology of Cancer 22. Distinguish between proto-oncogenes and oncogenes.

23. Describe three genetic changes that can convert a proto-oncogene to an oncogene.

24. Explain how mutations in tumor-suppressor genes can contribute to cancer (Figure 18.23). 5

25. Explain how excessive can result from mutations in the ras proto-oncogene (Figure 18.24).

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