1. DNA

2. What is DNA? Polymer made of nucleotides Nucleotides are made of:
a simple sugar (deoxyribose sugar)
a phosphate group
a nitrogen base
It contains the code to make proteins!
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.
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3. DNA (deoxyribonucleic acid)
Found in nucleus
Coils to form chromosomes
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

4. Covalent bonds hold sugar and phosphate groups together
Hydrogen bonds hold nitrogen bases together
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

5. The Four Nitrogen Bases are
Adenine (A)
Thymine (T)
Guanine (G)
Cytosine (C)
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.
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6. Purines & Pyrimidines
Purines: Include bases Adenine & Guanine. Have a double ring structure.
Pyrimidines: include bases Thymine, Cytosine, and Uracil. Have a single ring structure.

7. Nitrogen Base Pairs Adenine pairs with thymine.
A bonds to T
T bonds to A
Guanine pairs with cytosine.
C bonds to G
G bonds to C
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

8. Hydrogen bonds weak bonds hold nitrogen bases together
bonds A -T and G - C
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

9. Watson and Crick
1950’s
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.
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10. Watson and Crick Discovered the structure of DNA
DNA is double stranded
Forms double helix spiral ladder

11. Watson and Crick A bonds to T C bonds to G They discovered that :
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.
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12. Order of the nitrogen base pairs is the genetic code.
Order of the nitrogen base pairs (A,T,G,C) determines the traits of the individual.
Order of the nitrogen base pairs is the genetic code.
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

13. Replication of DNA Process of copying DNA Takes place in nucleus
Happens before cells divide by mitosis or meiosis
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

14. DNA Replication

15. DNA Replication
Allows daughter cells formed from mitosis to be identical to parent cell.
Allows four sex cells with ½ the genetic material ( ½ the number of chromosomes) to be formed in meiosis
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

16. How DNA Replicates Hydrogen bonds break (Helicase)
DNA molecule unzips between nitrogen base pairs (A-T or T-A and C-G or G-C)
Nucleotides (Nitrogen base, sugar, and phosphate groups) move from cytoplasm into nucleus
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

17. Replication of DNA
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.

18. How DNA Replicates (cont’d)
Nucleotides moving into nucleus bond with original strands of separated DNA (DNA Polymerase)
Two strands of DNA are formed
Each double stranded DNA molecule has one strand of old and one strand of new DNA (semi-conservative process).
Miller, K. R., & Levine, J. S. (2005). Chapter 12: DNA and RNA. Prentice Hall biology (North Carolina ed., pp ). Upper Saddle River, N.J.: Prentice Hall.