1. 3.4 The DNA Connection
Mutations

2. Mutation: a change or mistake that is made on chromosomes/DNA, during cell division.
During cellular division or meiosis, the cell copies its chromosomes/DNA before it divided into two identical cells.
Sometimes a mistake, or mutation, occurs.
Ex.

3. 3 types of DNA mutations
Substitution
Addition (Insertion)
Deletion

4. Chromosome Mutations
Ex. Down Syndrome: a genetic condition resulting from an abnormal # of chromosomes (trisomy 21)

5. Good, Bad, or Neutral ?
Mutations result in the production of “different” proteins in an organism.
Sometimes they are fatal (self-terminating pregnancy)
Sometimes they are neutral (6-toed house cat)
Sometimes they are an advantage (white polar bears)