Today is Tuesday, November 19 th , 2013

1. In This Lesson: Unit 5 DNA Structure and Replication (Lesson 1 of 3) Today is Tuesday,November 19th, 2013 Pre-Class: Today we start DNA. Tell me everything you know about it. You must write this down (the more scientific, the better). (But write down everything you can) What are the names of all the DNA bases we’ve learned so far? Also, today is our Strawberry Lab. It’s in the turn-in box – go get a copy! Also get a small paper towel. www.savagechickens.com

2. Today’s Agenda • Strawberry DNA Extraction • Where we are and where we’ve been • Challenge Questions • DNA Structure • DNA Replication • As in, what happened in S phase. • DNA Pickup Line? • Where is this (all) in my book? • Pages 291-308

3. Strawberry DNA • The most delicious DNA out there…

4. Orientation • First, we studied atoms. • Atoms make up all matter. • Some of this matter is considered organic, and is organized into four major groups. • Life-supporting organic matter has non-living functions, like diffusion and osmosis.

5. Orientation • Diffusion and osmosis help living things carry on life and undergo respiration. • Life’s smallest unit is the cell. • There are prokaryotes and eukaryotes, and they all have different organelles. • Even among eukaryotes, there are plant cells and there are animal cells.

6. Orientation • All cells, however, need to grow and reproduce. • For body cells (also known as somatic cells), growth occurs through mitosis. • Mitosis is a process in which the genetic material (DNA) is copied and the nucleus (and right after, the cell) divides.

7. Orientation • Sex cells (or gametes), use the process of meiosis. • The chromosomes in your cells are made of DNA, which makes you who you are. • Today we will begin learning about how DNA copies and how it “codes” for proteins, which is the molecular basis for genetics.

8. Challenge Questions • To the whiteboards!

9. Introducing DNA • Video: DNA Introduction

10. DNA’s Discovery • Discovered by Friedrich Miescher in 1869. • Noticed something in pus in discarded surgical bandages. • Called it “nuclein,” but other than a guess didn’t know it had any role in heredity. Johann Friedrich Miescher http://upload.wikimedia.org/wikipedia/commons/b/bc/Friedrich_Miescher.jpg

11. DNA’s Discovery Francis Crick James Watson • DNA’s structure was discovered in 1953 by: & Maurice Wilkins And all three were exploiting the work of… With some big help from… Rosalind Franklin http://www.nobelprize.org/nobel_prizes/medicine/laureates/1962/wilkins.jpg http://sciencecomm.wikispaces.com/file/view/3441067.jpg/96607078/3441067.jpg http://www.floridahumanist.org/images/FrancisHarryComptonCrick.jpg http://www.nobelprize.org/nobel_prizes/medicine/laureates/1962/watson.jpg

12. DNA Overview Video • Video: DNA Overview • Video: TED – Judith Hauck – The Twisting Tale of DNA

13. DNA • The big important statement: • DNA in a long strand and wrapped around proteins is called chromatin. When condensed, a piece of chromatin is called a chromosome. • Segments of the DNA strand are called genes. These genes tell the cell what proteins to make, which determine your traits. • Genes are like chapters in the book of DNA. • Each cell has the whole book, but depending on their jobs, the cells read different chapters.

14. DNA and Review • DNA is a nucleic acid, a long string of nucleotides. • DNA takes the shape of a double-helix. • There are four kinds of nucleotides: • Adenine • Cytosine • Guanine • Thymine http://ghr.nlm.nih.gov/handbook/illustrations/dnastructure.jpg

15. Nucleotide Review • Each nucleotide has a: • Sugar molecule with 5-carbons (pentose) • Deoxyribose in DNA • Ribose in RNA • Phosphate group • Phosphorous-based molecule • Nitrogenous base (makes the nucleotide unique) • Adenine • Thymine • Cytosine • Guanine

16. SKETCH ME! I’m useful! SKETCH ME! I’m useful! Nucleotide Structure Review SKETCH ME! I’m useful! SKETCH ME! I’m useful! Guanine Adenine Thymine Cytosine http://www.biologyjunction.com/images/nucleotide1.jpg SKETCH ME! I’m useful! SKETCH ME! I’m useful!

17. Nucleotide Structure Review • More “scientific”

18. Nucleotides and Nucleosides • Just so you know, you’ll occasionally hear of a nucleoside. • The only difference between a nucleoside and a nucleotide is that a nucleoside is just a sugar and nitrogenous base – no phosphate group.

19. DNA • Surrounding the base pairs and forming the sides of the “ladder” is a sugar-phosphate backbone. • The backbone is made of an alternating pattern of sugars (deoxyribose) and phosphate groups. http://ghr.nlm.nih.gov/handbook/illustrations/dnastructure.jpg

20. DNA • DNA stands for Deoxyribonucleic Acid. • By hydrogen bonds, cytosine bonds to guanine and adenine to thymine. • A ↔ T • C ↔ G http://ghr.nlm.nih.gov/handbook/illustrations/dnastructure.jpg

21. Base Pairs • (Held together by hydrogen bonds) • How can we remember this?

22. P Deoxy-ribose ---H--- Deoxy-ribose Adenine DNA Unwound (Basic) P P P P Deoxy-ribose Deoxy-ribose Deoxy-ribose ---H--- Cytosine Adenine Guanine Thymine One Nucleotide P Deoxy-ribose ---H--- Thymine

23. P 5’ 3’ Deoxy-ribose ---H--- Deoxy-ribose Thymine DNA Unwound(Advanced) PD Bond P P P P PD Bond Deoxy-ribose Deoxy-ribose Deoxy-ribose ---H--- Adenine Adenine Cytosine Guanine PD Bond P PD Bond Deoxy-ribose ---H--- Thymine 5’ 3’

24. Complementary Base Pairs • Video: DNA Complementary Base Pairs

25. DNA Worksheet • Try problems 1 and 2 on your DNA worksheet. 1: A C 1: T G 2: G A A G G C G T T

26. DNA • Adenine and guanine are purinesand have a double-ring structure. • Cytosine and thymine are pyrimidines and have a single-ring structure. • A purine always bonds to a pyrimidine. • How can we remember this one?

27. DNA Worksheet • Try problems 3, 4, and 5 on your worksheet. 3: T T G C A A G T C 4: 5. Always three rings (keeps the same width).

28. DNA Worksheet • Try problems 6 and 7 on your worksheet. 6: Sugar/Phosphate Backbone 7: A ↔ T, C ↔ G 7: Purines – 2 rings, Pyrimidines – 1 ring

29. DNA Replication • There comes a time in (almost) every DNA molecule’s life when it needs to be replicated (copied). • That time would be S phase. • DNA must be copied before mitosis. • Here’s the general process: • Unwind the double-helix. • Break the hydrogen bonds (“unzip” the DNA). • Use enzymes to replace base pairs on each side.

30. Looks like this… [IMPORTANT] Note that even though there are two strands forming down here, each is only “half” new. The “old” strand is sometimes known as the template strand because it’s a model for the new one.

31. Looks like this… [IMPORTANT] http://online.santarosa.edu/homepage/cgalt/BIO10-Stuff/Ch10-Protein_Synthesis/DNA-Replication-Animation.gif

32. DNA Replication - Schematic • Video: DNA Replication – Schematic

33. Time for a Game! • In this game, you will be practicing the process of replication. • Don’t mess up the base pairs! • You’ll also use the DNA you make to figure out which organism it comes from. • http://nobelprize.org/educational/medicine/dna_double_helix/dnahelix.html

34. Adding some names… • In that activity, we matched DNA bases to one another. Ts were with As, Gs with Cs. • Because they go together, we call these pairings complementary. • “The complementary base of G is C.”

35. Enzymes • The role we played – breaking the DNA “ladder” and replaced missing base pairs – is a role played by enzymes in the human body. • There are two main enzymes: • DNA Helicase • Unzips the DNA double-helix (breaks H-bonds). • DNA Polymerase • Adds complementary base pairs.

36. DNA Helicase Animation http://gifsoup.com/view/1504259/dna-helicase.html

37. DNA Replication – Molecular • Video: DNA Replication – Molecular

38. P Deoxy-ribose Deoxy-ribose H H ---H--- Adenine Replication P P P P P P P P P P P P DNA Helicase breaks H-bonds DNA Polymerase makes new DNA Strands move apart Deoxy-ribose Deoxy-ribose Deoxy-ribose Deoxy-ribose Deoxy-ribose Deoxy-ribose Deoxy-ribose Deoxy-ribose Deoxy-ribose H H Cytosine Adenine Guanine Cytosine Thymine Thymine Guanine Adenine Thymine Adenine ---H--- P Deoxy-ribose H Thymine ---H--- H

39. Enzymes • For your information, there are also two other enzymes: • DNA Ligase • Seals up breaks in the DNA code that occur naturally during replication. • RNA Primase • Lays down a “primer” after which DNA Polymerase can start to work. • I will not hold you to these on the quiz/core, but they will come up.

40. What We Know About DNA • We always hear that DNA is the genetic material of the cell, or the command center, or what is responsible for you. Whatever. What exactly does that mean? • DNAhelps the cell “decide” which proteins to make. • The proteins are different for everyone. • That’s why your DNA makes you unique. • And why we can use DNA to test potential criminals.

41. Time for a Flowchart • Find some room in your notebooks.

42. Guiding Question • How can one person have two different eye colors? • Your questions? What do you want to know?

43. Time for a Gizmo • It’s called Building DNA, and that’s just what you’ll be doing. • As usual, you’ll need a second window open for Quia: • Building DNA Gizmo • [Log-in Instructions]

44. Exit Ticket (Part One) • What are the full names of the four nitrogenous bases in DNA? • Which are purines, which are pyrimidines? • Which bases pair to which?

45. Exit Ticket (Part Deux) • Which enzyme “unzips” the DNA double helix? • Which enzyme places new nucleotides to complete the base pairs?