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Chapter 11
How Are Genes Expressed?
THEMES AND OBJECTIVES
The following is a list of the main themes covered in this chapter and some study objectives. As
you study, focus on these areas. Understand how the information you study fits into these themes
and how these themes relate to each other. Be sure you master each objective before moving on.
1.
After Watson and Crick published the structure of DNA, tremendous effort went into
explaining how DNA leads to protein synthesis.
 Review the history of this scientific quest for knowledge.
2.
Protein synthesis involves two distinct processes: transcription and translation.
 Thoroughly explain each process in terms of location, participants, events, and results.
 Compare and contrast these processes in prokaryotes and eukaryotes.
 Discuss differences in the three types of RNA, and compare their structure to DNA.
 Discuss the structure and role of ribosomes in translation.
 Discuss how errors in this process can lead to mutations.
3.
All cells contain all of an organism's genes, yet those genes are not all expressed. So cells
require mechanisms by which to regulate gene expression.
 Discuss the various levels at which cells can exert control over gene expression.
 Differentiate between gene regulation in prokaryotes and eukaryotes and explain why
eukaryotic regulation is more complicated.
 Thoroughly explain the lac operon and how it functions.