Bio3400 Chapter 14 Translation and Proteins
  1. Translation requires        acids,            RNA (mRNA), ribosomes, and           RNA ( tRNA ).

  2. Each tRNA is "charged" with a specific amino acid by 20 different aminoacyl tRNA              .

  3. Translation of mRNA can be divided into three steps.
    •             requires the        and        ribosomal subunits, GTP, initiator tRNA, and initiation          .

    •             requires both ribosomal subunits assembled with the mRNA to form the    site and    site.

    •              is signaled by a       codon (UAG, UAA, UGA) in the A site.

  4. A mRNA molecule can have several            simultaneously translating the message, forming                ( polysomes ).

    Review: interactive polypeptide coding, translation steps, animation.
  5. Studies of mutations that result in heritable human diseases such as               and           provided first insight into the role of proteins in genetic processes.

  6. Studies of mutations in Neurospora led to the one-gene:one-         hypothesis.

  7. Studies of human             showed that one gene encodes one              .

    • Humans possess        different hemoglobin polypeptide genes; two of which are expressed at different times in development

  8. The order of nucleotides in a gene is           with the order of amino acids in the corresponding polypeptide.

  9. Amino acids are composed of a           group, an        group, and an R group bound to a central         atom.

  10. The          structure of a polypeptide is the sequence of amino acids formed by linking them together by          bonds.

  11. Proteins may also exhibit        additional levels of structure: secondary, tertiary, and quaternary.

  12. Proteins play diverse roles in the body.
    • Hemoglobin binds to and transports         , which is essential for cellular metabolism.

    • Collagen and keratin are             proteins.

    • Actin and myosin are              proteins in muscle tissue.
    •                  ( antibodies ) recognize "foreign" particles in the immune system.
    • Transport proteins move molecules across            .

    • Some           and their receptors are proteins.
    •           bind to DNA in eukaryotic organisms.
    • Enzymes act as            in biological reactions.