1. Mutations are changes in DNA that may or may not affect phenotype.

2. Some mutations affect a single gene, while others affect an entire chromosome.
A mutation is a change in an organism’s DNA.

3. Many kinds of mutations can occur, especially during replication.

4. Mutagens Agents in the environment that can change DNA. UV rays X-rays
Tobacco
Viruses

5. Point Mutation (Base-pair substitution)
substitutes one nucleotide for another
mutated
base

6. Frameshift Mutation
inserts or deletes a nucleotide in the DNA sequence
If nucleotide is inserted it can also be called Base insertion.
If nucleotide is deleted it can also be called Base deletion.
Cystic Fibrosis is caused by a specific deletion.

7. Chromosomal Mutation Chromosomal mutations affect many genes.
Chromosomal mutations tend to have a big effect.
Chromosomal mutations may occur through crossing over during meiosis.
Two types of chromosomal mutations:
Gene duplication
Gene translocation

8. Chromosomal Mutation
Gene duplication results from unequal crossing over.
Chromosome has two copies of a gene or genes.
Opposite of deletion.

9. Chromosomal Mutation
Translocation results from the exchange of DNA segments between nonhomologous chromosomes.
Causes rearrangements without changing the chromosomal number
Causes changes to chromosome number-Downs Syndrome

10. Effects of Mutations Somatic Mutations Germ Mutations
Mutations in body cells (not passed from parent to offspring)
Usually silent but can dramatically affect an individual’s phenotype.
Skin and Lung cancers
Germ Mutations
Mutations in gametes, sex cells (can be passed from parent to offspring)
Affect the survival of an organism and change the traits of the organism’s descendants
Can be beneficial or harmful
Beneficial mutation may help an organism survive in a changing environment
Hemophilia and Color blindness