1. The DNA Code How does DNA affect living things?
What happens when a mistake occurs in DNA?

2. DNA Chromosomes found in the nucleus of the cell are made of DNA
DNA is a long strand of genetic material
Made of the bases Adenine (A),
Thymine (T), Cytosine (C) and
Guanine (G)
These bases encode instructions
that allow your body to function

3. The DNA Code
Parts of your DNA are genes that carry instructions for making the proteins that help build an organism
The bases are divided into 3 letter codons that code for the 20 amino acids that build proteins
After the protein is built in the cell, it is released to do its job

4. What happens if a mistake occurs?
A mutation is a mistake that occurs in the sequence of DNA
Mutations cause proteins to form incorrectly or not at all, causing a disruption in the cell’s function

5. Types of Mutations
Substitution: exchanges one base for another
Ex: DNA that reads ATCG now reads AACG
Insertion: extra bases are inserted into a new place in the DNA
Ex: DNA that reads ATCG now reads ATTCG
Deletion: a piece of DNA is erased completely
Ex: DNA that reads ATCG now reads AT

6. How do Mutations Affect an Organism?
Mutations can be helpful, harmful or cause no effect to an organism
Helpful Mutations are beneficial
People with only one copy of the sickle-cell anemia gene are resistant to malaria

7. How do Mutations Affect an Organism?
Harmful Mutations cause problems/disease
Cancer usually results from a series of mutations within a single cell

8. How do Mutations Affect an Organism?
Neutral Mutations cause no effect on the organism
Red Hair is a mutation in humans that does not affect the person’s ability to survive and reproduce

9. Homework Draw a representation of DNA. Identify the bases and codons.
What does a codon code for? What would happen if a codon was changed?
List and describe three different types of mutations.