2. Bell Ringer 1.What does D.N.A. stand for? 2.What is the function of D.N.A. ?

3. Joke of the Day: 2

4. 3 DNA: The Blueprint of Life

5. 4 DNA Deoxyribonucleic AcidDeoxyribonucleic Acid T.The blueprint of life. DNA contains the instructions for making proteins within the cell.

6. DNA In Eukaryotes, DNA is found in the nucleus. It can leave the nucleus during cell division, but it never leaves the cytoplasm. 5

7. James Watson and Francis Crick’s Model Called a Double Helix. DNA is a very long polymer. DNA has TWO strands twisted together.

8. 7 DNA Analogy: “Twisted Ladder” And/Or “Zipper”

9. 8 One Strand of DNA One strand of DNA is a polymer of nucleotides. One strand of DNA has many millions of nucleotides. nucleotide

10. 9 Nucleotide: 3 Parts CC C O Phosphate O C C O -P O O O Deoxyribose sugar Phosphate Nitrogenous base. Nitrogenous base Deoxyribose

11. 10 Four nitrogenous bases Cytosine C Thymine T Adenine A Guanine G DNA has four different bases:

12. 11 Two Kinds of Bases in DNA Purines are double ring bases.Purines are double ring bases. Pyrimidines are single ring bases.Pyrimidines are single ring bases. C C C C N N O N C C C C N N N N N C

13. 12 Purines: A = Adenine G = Guanine C C C C N N N Adenine N N C C C C C N N O N Guanine N N C

14. 13 Pyrimidines: T = Thymine C = Cytosine C C C C N N O N cytosine C C C C N N O O thymine C

15. DNA Structure 14 Hydrogen bonds Nucleotide Sugar-phosphate backbone Key Adenine (A) Thymine (T) Cytosine (C) Guanine (G)

16. 15 One Strand of DNA The “sides” of the ladder are alternating Phosphates and Deoxyribose Sugars The “rungs” are Nitrogenous Bases. The Nitrogenous Bases are held together by Hydrogen Bonds phosphate deoxyribose bases

17. 16 Two Stranded DNA DNA has two strands that fit together something like a zipper. The teeth are the nitrogenous bases but why do they stick together?

18. 17 Chargaff’s Rule: Adenine and Thymine always join together A T Cytosine and Guanine always join together C G

19. 18 C C C C N N O N C C C C N N O N N N C Hydrogen Bonds The bases attract each other because of hydrogen bonds. Hydrogen bonds are weak but there are millions and millions of them in a single molecule of DNA. The bonds between cytosine and guanine are shown here with dotted lines

20. 19 DNA by the Numbers Each cell has about 2 m of DNA. The average human has 75 trillion cells. The average human has enough DNA to go from the earth to the sun more than 400 times. The earth is 150 billion m or 93 million miles from the sun.

21. 20

22. 21 Bell Ringer: 1.Where is DNA located in the cell? 2. What did Watson and Crick call DNA’s structure? 3. How many strands are in a DNA molecule? 4. Draw and label the 3 parts that make up a nucleotide? 5. What are the 4 nitrogenous bases and their abbreviations? 6. What is Chargaff’s Rule? 7. Write a complementary code for the following strand of DNA. GATTACAGATTACA CTAATGTCTAATGT

23. 22 Joke of the Day:

24. 23 Joke of the Day #2:

25. 24 DNA Origami

26. 25 http://www.youtube.com/watch?NR=1&v=8kK2zwjRV0M&feature=endscreen DNA Video 13 Minutes

27. 26 Quick Closure: 1.Where is DNA located in the cell? 2. What did Watson and Crick call DNA’s structure? 3. How many strands are in a DNA molecule? 4. What 3 parts make up a nucleotide? 5. What are the 4 nitrogenous bases and their abbreviations? 6. What is Chargraff’s Rule?

28. 27 Joke of the Day: