8.7 Genetic Mutations and Their Effects

Front

Explain why frameshift mutations have a greater effect than do point mutations.

Back

Point mutations typically affect only one codon (unless they create a premature stop codon). A frameshift mutation affects all the codons in a gene that follow it.

Front

If GUA is changed to GUU, will the resulting protein be affected? Explain.

Back

No, both GUA and GUU code for the amino acid valine.

Front

Explain how mutagens can cause genetic mutations in spite of your body’s DNA repair enzymes.

Back

Mutagens may cause so much damage that the repair enzymes cannot keep up with the repairs.

Front

What might be the advantages and disadvantages of being tested for genetic mutations associated with diseases?

Back

Advantage: A person would know to look for symptoms and would be able to prepare and seek possible treatment. Disadvantage: There may be no cure for the disease, or simply having the gene may not mean that getting the disease is inevitable.

Front

Explain why mutagens can damage DNA in spite of repair enzymes.

Back

The mutagens can induce more mutations than the repair enzymes can fix.