3. Student Learning Map

  • Topic:07- Genetic Code
  • Subject(s):Science
  • Days:12
  • Grade(s):9
Key Learning:

DNA carries the genetic information of a cell and consists of thousands of genes. Each gene serves as a blueprint for building protein molecules. The structure of DNA allows for it to be quickly and accurately replicated so proteins can be synthesized.
Unit Essential Question(s):
 
 

What influence does DNA have the functions of a cell?
   
Concept:

Discovery of DNA's Structure

SC.912.L.16.9   SC.912.N.3.5   SC.912.N.1.4  

Discovery of DNA's Structure:

  • Describe the work of Watson, Crick, Wilkins and Franklin in discovering the structure of DNA.
  • Emphasize how the work of Wilkins and Franklin assisted Watson and Crick.
  • Reinforce the idea that scientific discoveries don't happen in isolation, they often build on previous work.

    • Describe the structure of DNA:

  • Examine the components of DNA including the nitrogenous bases (Adenine, Thymine, Guanine and Cytosine) and the sugar-phosphate backbone.
  • Use a visual or model to demonstrate the double helix structure of the DNA molecule.

    • Describe the function of DNA:

  • Discuss how the genetic code is universal to almost all organisms.
  • Examine the function of DNA. Emphasize that DNA stores an organism's genetic information and controls the production of proteins and is thus responsible for the biochemistry of an organism.
    •
    Concept:

    Protein Synthesis

    SC.912.N.3.5   SC.912.L.16.5   SC.912.L.16.3  

    DNA Replication:

  • Describe the process of DNA replication.
  • Recognize the function of DNA polymerase in the replication process.
  • Emphasize the end product of DNA replication. When the replication process is complete one of the new strands of DNA is zipped with the corresponding original strand. This will produce two molecules of DNA, each an exact copy of the other.
  • Allow students the opportunity to build a DNA molecule and replicate it.

    • Structure of RNA:

  • Describe the structural difference between DNA and RNA.
  • Explain that RNA is only a single strand, the sugar used in the sugar-phosphate backbone is ribose and that RNA has four nitrogenous base pairs (Adenine, Uracil, Cytosine and Guanine).

    • Transcription:

  • Discuss how messenger RNA (mRNA) is formed when the DNA is strand is unzipped and corresponding RNA bases are brought in to match the corresponding DNA bases.
  • Explain that when transcription is done, the mRNA strand leaves the nucleus and goes to the cytoplasm and the DNA rejoins back into a double helix.
  • Allow students the opportunity to build corresponding DNA and mRNA chains.

    • Translation:

  • Explain how the mRNA strand is used by ribosomes to assemble chains of amino acids which form proteins.
  • Discuss how during translation transfer RNA (tRNA) is used to bring in the various amino acids needed for protein synthesis.
  • Recognize the role of codons and anticodons in protein synthesis.
  • Using mRNA and a codon table have students build an amino acid chain.

    • Be sure to use visuals or diagrams to show the processes of replication, transcription and translation.

    HOTS: Comparing/Contrasting or Constructing Support could be used demonstrate the ET LEQ
    Concept:
    Lesson Essential Question(s):

    What events led up to the discovery of the structure of DNA?

    (A)

    How can you describe the structure and function of DNA?

    (A)
    Lesson Essential Question(s):

    What is the relationship between the structure of DNA and DNA replication?

    (A)

    How are mRNA and tRNA useful in protein synthesis?

    (A)

    How do transcription and translation work together to form an amino acid chain?

    (ET)
    Lesson Essential Question(s):
    Vocabulary:

    *DNA

    Vocabulary:

    *amino acid, protein synthesis, *protein, *RNA- ribonucleic acid, transcription, translation

    Vocabulary:

    Additional Information:

    The asterisk (*) next to the vocabulary terms above indicates essential FCAT vocabulary.

    Refer to Holt Modern Biology textbook chapters 9-10 (pages 172-215), chapter 11 (pages 225-228) and ancillary materials.

    GIZMOS: "RNA and Protein Synthesis", "DNA Fingerprint Analysis", "Building DNA"

    View As PDF

    Acquisition Lesson:

    Extending Thinking Lesson:

    Vocabulary Report

    • *amino acid -

      An organic molecule containing an amino (-NH2) and a carboxyl (-COOH) group from which proteins are synthesized.

    • *DNA -

      A nucleic acid that carries genetic material; present in all cellular organisms.

    • protein synthesis -

      The formation of proteins by using information contained in DNA and carried by mRNA.

    • *protein -

      A biological macromolecule composed of one or more chains of amino acids.

    • *RNA- ribonucleic acid -

      A natural polymer that is present in all living cells and that plays a role in protein synthesis.

    • transcription -

      The process of forming a nucleic acid by using another molecule as a template; particularly the process of synthesizing RNA by using one strand of a DNA molecule as a template.

    • translation -

      The portion of protein synthsis that takes place at ribosomes and that uses codons in mRNA molecules to specify the sequence of amino acids in polypeptide chains.