1. Mutations

2. DNA Mistakes DNA is a molecule that replicates, works and copies with very high accuracy DNA has enzymes that make sure that it works with a high level of accuracy and detail DNA can often work without mistake

3. DNA Mistakes DNA can however make mistakes When a DNA makes a mistake in its own sequence of base pairs its is called a mutation A mutation can change the base pairs in DNA for the rest of DNA

4. DNA Mistakes The process of making mutations is called mutagenesis Mutagenesis is often the result of physical or chemical agents that can damage DNA called mutagens

5. Substitution One of the types of mutations makes mistakes between the base pairs When a base pair does not correctly match put with its complement it is a substitution mutation

6. Example Original Phrase: The cat ran over the hat. Mutation: cat  bat New Phrase: The bat ran over the hat.

7. Substitution If a substitution mutation is made, however there is no change in the amino acid sequence it is called a silent mutation This is because the mutation in not seen If the mutation does change the amino acid sequence it is called a missense mutation

8. Results of Mutations Often times mistakes can change the stop codons for proteins This means proteins either end early or don’t end at all When a stop codon is changed and it changes the shape of an amino acid sequence it is called a nonsense mutation This type of mutation can permanently change the organism

9. Substitution By substituting a base pair for a different base pair will change the codon in the mRNA By changing the codon there is a different amino acid that is coded This changes the overall protein that is stored in DNA

10. Insertion and Deletion Sometimes extra base pairs can be added or deleted from the DNA strand These additions or decreases in base pairs can affect the entire molecule of DNA This can change the message of DNA These are called frameshift mutations

11. Example Original Phrase: The cat ran over the hat. Mutation: ran  rn New Phrase: The cat rno vert heh at.

12. Insertion and Deletion By adding and deleting base pairs there is a change in the overall codons for the protein It could change some or all of the amino acids in the protein Depending on where the insertion and deletion happens it could ensure that the protein never starts or stops

13. Video http://www.youtube.com/watch?v=kp0esidDr- c

14. Results of Mutations Mistakes in DNA often present themselves in single base pairs One single base pair can change the message for an entire protein These changes can change the proteins that DNA codes for

15. Results of Mutations People often think about mutations in the way that the media presents mutations People often think that mutation give people different personalities or powers http://www.youtube.com/watch?v=DI7q6DF6 D54

16. Results of Mutations Many times when a cell undergoes a mutation a cell becomes of less value The cell cannot create a functional protein in a segment of DNA This makes the cell less effective

17. Results of Mutations Mutations also often lead to the death of a cell Without an essential protein a cell will die If the cell is very important, it could lead to the death of the organism

18. Mutations in Evolution Mutations are not all bad If the mutations give the organism some benefit the organism could live The organism might actually benefit from the overall mutation

19. Practice