1. Objective: 1)Describe the structure of DNA: A.Understand that DNA is a biological macromolecule B.Understand that DNA strands (polymers) are made up of nucleotides (monomers) C.Understand that DNA is double-stranded and twisted into a “double helix” D.Understand that nucleotides are made up of a sugar, a nitrogenous base, and a phosphate group E.Understand that DNA strands are held together by hydrogen bonds between base pairs F.Understand that there are four different DNA nucleotides (A, T, C, & G) G.Understand that the complementary base pairing rule specifies that A’s bond with T’s and C’s bond with G’s H.Understand that the outer part of the helix is made up of the sugar-phosphate backbone of each strand and the inner part of the helix is made up of the base pairs

2. Agenda Wednesday 10/21/15 1)Warm-Up 2)DNA Structure Lecture (Finish) 3)DNA Structure Textbook Assignment (Start)

3. Week 11 Warm-Up Wednesday 10/21/15: (Write the question.) What is the difference between a DNA double helix and a DNA nucleotide?

4. Possible Answer #1. “I don’t know.” - F

5. Possible Answer #2. “A DNA double helix is a polymer and a DNA nucleotide is a monomer.” - C

6. Possible Answer #3. “A DNA double helix consists of two polymer strands, each made up of millions of nucleotides. The two strands are bonded together and twisted into a“double helix”, or spiral shape. A DNA nucleotide is a monomer, or small molecule, that makes up the links in the DNA polymer chains. Bonds between nucleotides hold the DNA double helix together.” - A

7. DNA Structure See, Hear, Read, Know

8. Chunking Lecture Notes: Rewrite Question into Answer Answer Questions 1-12 Draw Pictures 13i-13iii

9. 1) What is this structure? The DNA is located in the nucleus of each cell.

10. 2) Where is DNA located in the cell? DNA is a nucleic acid, the 4 th biological macromolecule.

11. 3) What are the four biological macromolecules? DNA stands for deoxyribose nucleic acid. One macromolecule of DNA is made up of millions of monomers.

12. DNA monomers are called nucleotides and contain three parts: a deoxyribose sugar a nitrogenous base a phosphate group 4) What does DNA stand for?

13. 5) What are the three parts of a nucleotide? There are four different nucleotides that make up all DNA: Adenine (A) Thymine (T) Cytosine (C) Guanine (G)

14. DNA is made up of two polymer chains that are bonded together and twisted into a “double helix”. 6) How many different DNA nucleotides are there?

15. 7) What shape does DNA have? The nucleotides on one strand of DNA can only bond with specific nucleotides on the other strand. A only bonds with T C only bonds with G

16. 8) What special rules are there in nucleotide bonding? There are two types of nucleotide bases: Pyrimidines: One nitrogenous ring (larger) Purines: Two nitrogenous rings (smaller)

17. 9) What’s the difference between a purine base and a pyrimidine base? The two strands of DNA are held together by chemical bonds between the (+) Hydrogens and (-) Nitrogens and Oxygens A and T bond at TWO locations C and G bond at THREE locations 10) Notice that each pair has one large and one small base. Why do you think this is?

18. 11) What’s the difference between the bond between A and T and the bond between C and G? This is called complementary base pairing. In the DNA double helix, base pairs are in the middle. Two strands WILL NOT bond into a double helix unless the bases are complementary.

19. 12) What is the special relationship between specific nucleotide bases called? Bases within one strand can line up and bond together in any order. Nucleotides in one strand are bonded together between the deoxyribose sugar and phosphate groups. This is called the “sugar phosphate backbone”.

20. 13) Draw and label all the parts of the following: i)Nucleotide showing the three parts ii)Strand of DNA showing sugar-phosphate backbone iii)DNA double helix showing complementary base pairing

21. Blue Owl Textbook: Section 10.2 DNA Structure 1)Read Section 10.2 in the blue owl textbook, pages 196- 199. (5-10 minutes) 2)Write a one sentence summary of each paragraph (14 total). (15 minutes) 3)Define the Vocabulary words on page 196. (10 minutes) 4)Answer Section Review questions 1-6 and 8-9. (15 minutes)