1. Changes in DNA
TEK 6E:
identify and illustrate changes in DNA and evaluate the significance of these changes

2. Mutations are ANY changes in the genetic material.
General Info
Mutation can be harmful, helpful or neutral in their effect. Mutations create genetic variation.
Mutations are ANY changes in the genetic material.
A mutation that occurs in the gametes will most likely be transferred to the offspring
Albinism
Rare genetic Mutation
Syndactyl

3. Gene vs. Chromosomal mutations
Gene Mutations:
Gene mutations result from changes in a single gene.
A change in one base; aka point mutation.
Point Mutations: Change of a single nucleotide. There’s two types:
Substitution
Frameshift
Chromosomal Mutations:
A mutation involving a long segment of DNA. These mutations can involve deletions, insertions, or inversions of entire sections of chromosomes.

4. Gene Mutations: Substitution
Substitution: Change in the nucleotide

5. Gene Mutations: Frameshift (Insertion or Deletion
In an insertion, an extra base is inserted into the base sequence.
The loss of a single letter shows the effect of a deletion.
Deletion

6. Chromosomal Mutations
Five types exist:
1. Deletion: removes a chromosome segment
2. Inversion: reverses a segment within a chromosome
3. Translocation: moves a segment from one chromosome to another, non-homologous one
4. Duplication: repeats a segment
5. Non-disjunction: chromosomes fails to separate properly during meiosis

7. Chromosomal Mutations

8. Causes & Significance of Mutations
spontaneously – errors that occur during replication and transcription
2. by a mutagen – an agent that causes a mutation
a. examples
 radiation – UV, x-rays, nuclear
 chemicals – smog, alcohol, tar, cigarette
 viruses – insertion of new DNA
Importance of Mutations – only original source of variation in the gene pool.
[can create genetic diversity]

9. QR Quiz