5.1 Chapter Objectives

Our goal for this chapter is for you to gain an understanding of the molecular basics of gene expression—the structure of DNA and RNA, along with how genes direct the synthesis of proteins, and how genetic mistakes (mutations) can affect these outcomes. By the end of your reading and our in-class discussion, you will be able to:

1. Define the following terms:
   • Nucleotide
   • Purines
   • Pyrimidines
   • Nitrogenous bases
   • RNA
   • mRNA
   • tRNA
   • rRNA
   • Transcription
   • RNA polymerase
   • Translation
   • Polypeptide
   • Mutation
   • Substitution
   • Deletion
   • Frameshift
   • Insertion
   • Nucleic acid
   • Chromosome
   • Ribosome
   • Heredity
   • Amino acid
   • Peptide
   • Protein
   • Genetics
   • Zygote
   • Codon
   • Allele
2. Describe the general structure of DNA.
3. Identify three types of RNA that are involved in gene expression.
4. Explain, using the genetic code, how DNA codes for proteins.
5. Describe a few of the many functions of proteins.
6. Derive the amino acid sequence of a polypeptide, based on DNA or RNA nucleotides.
7. Describe how different types of point mutations (substitution, deletion, insertion) can affect gene expression.
8. Evaluate whether there is such a thing as “gene for monogamy.”