1. Mutation, Natural Selection, and Artificial Selection

2. Mutation is a change in DNA sequence
Change in DNA  change in protein  change in organism
Mutation can be positive, negative or neutral.
Mutagen: a physical or chemical agent that changes the DNA

3. Types of Mutations Gene
change in the nucleotide sequence, in a particular gene
2. Chromosomal
is a change in several genes
segments of chromosomes, whole chromosomes, or entire sets of chromosomes change

4. Gene Mutations Types: Point mutation
change in ONE nucleotide base of the DNA sequence
The change in the DNA is minor but important
Ex) Substitution – change of one base to another base

5. 2. Frameshift Mutation
a single base is added or deleted from DNA which shifts the reading of codons by one base.
The results of frameshift mutations can be HUGE since every codon after the mistake is affected!
Ex) Insertion – one base is added
Ex) Deletion – one base is removed

6. Chromosomal Mutations
4 main types:
Deletion: part of a chromosome left out
Insertion: additions to a chromosome
Inversion: chromosome part breaks off & reattaches backwards
Translocation: chromosome part breaks off & adds to another chromosome

7. Mutation can be positive, negative or neutral.
Positive: antibiotic resistance in bacteria increases survival

8. Negative: duplication of codons in Huntington’s disease gene causes the protein to work incorrectly, decreasing survival

9. Neutral: change in DNA that does not cause a change in protein (silent) or changes something that does not affect survival

12. Can depend on environment whether a mutation is +, -, or neutral
Ex. Sickle Cell Anemia