1. DNA Structure

2. Where is DNA located?
In the nucleus

3. DNA Made of nucleotides Phosphate group 5 carbon sugar (deoxyribose)
Nitrogen base
DNA nucleotide

4. Purines
Two rings
Adenine (A)
Guanine (G)

5. Pyrimidines
One ring
Cytosine (C)
Thymine (T)

6. The base pairing rule A bonds with T G bonds with C
How are they joined?
Hydrogen Bonds

7. How are they joined?
Hydrogen Bonds

8. Complementary strands
Sequence of bases on one strand determines the sequence of bases on the other
Allows for DNA replication (copying)

9. Why is this important?
Allows for DNA replication (copying)

10. The 2-D shape of DNA
Resembles a ladder

11. The rails or “backbone” The rungs
phosphate & sugar
The rungs
nitrogen bases

12. 3-D shape of DNA Double Helix aka winding staircase 2 Strands twisted
around each other

13. Antiparellel
One strand goes one way and the other goes the opposite