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Chapter 10: Gene Expression and Regulation At a Glance

Case Study: Boy or Girl?

10.1 How Are Genes and Proteins Related?

• Most Genes Contain the Information for the Synthesis of a Single Protein
• DNA Provides Instructions for Protein Synthesis via RNA Intermediaries
• Overview: Genetic Information Is Transcribed into RNA, Then Translated into Protein
• The Genetic Code Uses Three Bases to Specify an Amino Acid

10.2 How Is Information in a Gene Transcribed into RNA?

• Initiation of Transcription Occurs When RNA Polymerase Binds to the Promoter of a Gene
• Elongation Proceeds Until RNA Polymerase Reaches a Termination Signal
• Transcription Is Selective

10.3 How Is the Base Sequence of a Messenger RNA Molecule Translated into Protein?

• Messenger RNA Carries the Code for Protein Synthesis from the Nucleus to the Cytoplasm
• Ribosomes Consist of Two Subunits, Each Composed of Ribosomal RNA and Protein
• Transfer RNA Molecules Decode the Sequence of Bases in mRNA into the Amino Acid Sequence of a Protein
• During Translation, mRNA, tRNA, and Ribosomes Cooperate to Synthesize Proteins
  Initiation: Protein Synthesis Begins When tRNA and mRNA Bind to a Ribosome
  Elongation and Termination: Protein Synthesis Proceeds One Amino Acid at a Time Until a Stop Codon Is Reached
• Recap: Decoding the Sequence of Bases in DNA into the Sequence of Amino Acids in Protein Requires Transcription and Translation

10.4 How Do Mutations in DNA Affect the Function of Genes?

• Mutations Result from Nucleotide Substitutions, Insertions, or Deletions
• Mutations May Have a Variety of Effects on Protein Structure and Function
• Mutations Provide the Raw Material for Evolution

10.5 How Are Genes Regulated?

• Proper Regulation of Gene Expression Is Critical for an Organism’s Development and Health

A Closer Look: Introns, Exons, and Splicing

• Eukaryotic Cells May Regulate the Transcription of Individual Genes, Regions of Chromosomes, or Entire Chromosomes
  Regulatory Proteins That Bind to the Gene’s Promoter Alter the Transcription of Individual Genes
  Some Regions of Chromosomes Are Condensed and Not Normally Transcribed
  Entire Chromosomes May Be Inactivated, Thereby Preventing Transcription

Health Watch: Sex, Aging, and Mutations

Case Study Revisited: Boy or Girl?

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