Class: Life Science, 10th Grade
Unit: Genes and DNA
Topic: Mutation

Instructional Objectives:
  • Students will be able to describe point mutations and how they affect the protein product. Students will be able to explain the difference between a silent mutation and one that changes an amino acid in the protein product.
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* Students will be able to describe a frameshift mutation and how that can change the length of a protein product as well as its constitution.
  • Given a mutated DNA sequence, students will be able to identify the mutation, describe the change in the resulting protein sequence, and speculate on the possible consequences.
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* Students will be able to describe chromosomal mutations and how they typicall result in the deletion or duplication of an entire gene. Students will understand that they are typically lethal.
  • Students will be able to compare mutations in reproductive versus somatic cells. They will be able to identify reproductive mutations as the ones that lead to differences in off-spring. They will be able to indentify somatic cell mutations as the ones responsible for causing cancer.
  • Students will be able to explain how mutations in DNA sequence may lead to disease in off-spring, such as sickle cell anemia.
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* Students will be able to explain how mutations in DNA sequence may not have consequences in off-spring.
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  • Students will be able to identify the three main types of mutagens: radiation, high temperatures, and chemicals. Students will be able to explain how exposure to mutagens can lead to cancer.
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* Students will be able to explain that there are DNA repair mechanisms and their role in preventing cancer.

Activity:

  1. Use color slides to show examples of genetic mutations. Show students images of human polydactyly, rodents with multiple tails, and fruit flies with antennae in the place of eyes.
  2. Use slides to show students the major types of mutations: point mutations, frameshift mutations, and chromosomal mutations.
  3. Put students in groups of two to do a handout in which they explore how insertions, substitutions, and deletions in DNA result in changes in proteins. Specifically, give the students DNA sequences, have them mutate the sequences according to the directions, and then transcribe and translate them.
  4. Discuss with the whole class how the different mutations affect the resulting protein products.
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# Use slides to describe the causes of mutations and the repair mechanisms.
  1. Use slides to explain the difference between somatic and gamete cell mutations and the role that they play in cancer and evolution respectively.

Assignment
  1. Given a description of the function of the genes, which the students mutated, transcribed and translated, and have them describe the likely consequence of the mutation.
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# Textbook, pp. 296-301 , "Genetic Changes"

Activity Materials Needed
None

Resources for Lesson
  1. Slides showing examples of genetic mutations
  2. Slides showing major types of mutations
  3. Mutation, transcription and translation handout
  4. Slides describing mutagens and repair mechanisms
  5. Slides to explain health and reproductive consequences of mutation

Genes and DNA Unit Lesson Sequence