MUTATIONS

MUTATIONS

MUTATIONS are changes in nucleotide sequence of DNA.

What causes mutations?

MUTAGENS

• Mutations are caused by MUTAGENS.

• MUTAGENS are physical or chemical treatments that change DNA.

Examples include: • UV light• Radioactive chemicals• Gamma Rays

MUTATIONS

• Permanently alter the base sequences of DNA.

• May have no effect, positive, or negative effect for organism.

• Sometimes a mutation occurs but still codes for the same amino acid.

• Mutations can occur at the gene level and the chromosomal level.

GENE MUTATIONS

• Point mutations: Change occurs at a single point in DNA sequence.

• Substitutions: One base is substituted (switched) with another.

• Usually only affects one codon, one corresponding amino acid

https://islaslab.wikispaces.com/Mutation

GENE MUTATIONS

• Frame-shift mutation: The codon sequence is altered. May affect more than one codon.

• Insertion: A base is inserted into the sequence without a replacement base.

• Deletion: A base is deleted from the sequence without a replacement.

http://web2.mendelu.cz/af_291_projekty2/vseo/stranka.php?kod=315

https://islaslab.wikispaces.com/Mutation

PB PG. 374 QUICK LAB “MODELING MUTATIONS”

Use the example provided in book on pg. 374 as a guide:

1. Start with the word gene and change it letter by letter to make new words. Make sure each new word is an actual word but not a proper noun. Write at least four (4) “point mutations” of the word gene.

2. Show how you could use words to model a frameshift mutation. (Hint: You can use a sentence.)

3. Use the words in this sentence to model a substitution mutation.