14.5: Mutations of One or a Few Nucleotides Can Affect Protein Structure and Function

14.5: Mutations of One or a Few Nucleotides Can Affect Protein Structure and Function

You Must Know: 

• How mutations can change the amino acid sequence of a protein and be able to predict how a mutation can result in changes in gene expression.

Key Terms: Point Mutations, Missense Mutations, Nonsense Mutations, Silent Mutations, Insertions, Deletions, Frameshift Mutation, Mutagens

Bellwork: Watch and take notes on " Mutations: The Potential Power of a Small Change" Amoeba Sisters video.

READING of Concept 14.5: Pages 298-300

1. Define the Key Terms above.

FROM PAGE 298-299

2. Create a graphic organizer that summarizes the 3 main types of point mutations (silent, missense, and nonsense).
3. Decide which type of point mutation typically leads to non-functional proteins.

FROM PAGE 300

4. Create a graphic organizer that summarizes the 2 main types of frameshift mutations (insertion and deletion).
5. Explain why frameshift mutations can have such potentially disastrous effects on the resulting proteins.
6. Describe 1 example of a physical mutagen.
7. Research and describe 1 example of a chemical mutagen that might be present in your home.
8. Explain the connection between carcinogens and mutagens.
9. The template strand of a gene includes this sequence: 3'-TACTTGTCCGATATC-5'. It is mutated to 3'-TACTTGTCCAATATC-5'. For both versions, draw the DNA (infer the coding strand), the mRNA, and the encoded amino acid sequence. What is the effect on the amino acid sequence? Determine which type of mutation this is.
10. Define what a gene is.