DNA_ RNA and Protein Synthesis_1_

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					DNA, RNA, and Protein Synthesis

Overview: Many students fail to appreciate the connection between nucleotide

sequence in DNA (genotype) and its’ effect on an organism’s characteristics

(phenotype). By understanding the possible consequences of a change

(mutation) in a human’s DNA (from as basic as physiological consequences, to

ethical considerations by society), students may come to recognize the influence

of DNA on characteristics that interest them.

Targeted Grade Level: 10th Grade

Science Standards: PA 3.3.10B, 3.3.10C.

                                      Stage I

Understandings: The proteins that are coded for by genes determine External

and Internal characteristics of living things, and changes in genes are

responsible for changes in those characteristics.

Essential Questions: What kind of changes in genes might be

beneficial/deleterious/not noticed? What kinds of characteristics can be affected

by changes in genes? Will knowing more about mutations and their effects help,

or hurt society?

Knowledge & Skill:
      Describe the relationship between the sequence of nucleotides in DNA

       and external (or internal) characteristics of an organism.

      Differentiate between genotype and phenotype.

      Distinguish between the various forms of mutation, and their possible


      Given a sequence of bases in a DNA molecule, use a genetic key to

       generate the proper amino acid sequence.

      Discuss whether it will be necessary to regulate, control, sanction, or

       monitor members of society that exhibit the symptoms or characteristics of

       a mutation.

                                       Stage II

Performance Tasks:

Each student in class may want to take on a role as a Senator or Representative

that is involved in a debate on legislation to screen individual citizens for genetic

disease, as a result from mutation. Questions/positions that may be taken:

      It’s better to know who suffers from the effects of a mutation, it allows

       agencies (governmental, private?) to offer services.

      Who should be privy to this information?

      What constitutes a mutation that deserves attention by specific agencies?

      What should be done if a mutation is found only in certain individuals that

       commit certain crimes (rape, violent crimes)?
       Would it be right to automatically “convict” someone if they were found to

        have this gene, but never committed a crime?

       Should health care providers be allowed to refuse coverage for someone

        who either suffers from or has the mutation for certain genetic diseases?

       Should there be legislation that limits the reproductive rights for individuals

        who suffer from/carry a certain mutation?

Each student (or small group, if it seems appropriate) will choose one item from a

list of genetic diseases (provided by the teacher). Their task is to research the

disease and present the following information to the class:

       Name of the disease

       Specific effect(s) (health or others) that this mutation has on an individual:

        Emphasis should be made on the specific type of mutation, and what

        changes this mutation makes (in amino acid sequence, protein

        structure/function, and/or phenotypic change in the individual).

       State a position, for or against, screening individuals for this mutation.

        Give specific benefits/detriments this policy would have (health care

        savings, infringing upon individual’s rights,etc.)

Other Evidence:

Traditional quizzes will be given to test knowledge of types of mutations, how the

DNA code is read to produce an amino acid sequence, and definitions of key

words (codon, gene, mutation, genotype, phenotype, etc.). Students (or groups)
will exchange, and be asked to write a response to, their peer’s position papers

from the “legislative” large assessment task.

                                     Stage III

Learning Activities include:

      Video: “The Power of Genes” (w/use of discussion questions as time


      Activity/Demonstration, “DNA Extraction from Wheat Germ”. Some

       discussion of the role of the extracted DNA in the function of the wheat

       plant would be useful: what is the DNA actually doing for the plant? What

       would happen if there were none/half/too much of this substance in the


      Activity: Assembling a Protein Molecule

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