1. Biology 1/21/14 Mrs. Turgeon “I have decided to stick to love. Hate is too great a burden to bear.” –Martin Luther King Jr. DO NOW: 1. 1. In your notes: How are the following terms related to one another? genes, chromosomes, traits, DNA AGENDA: 1. 1. Students will understand basic DNA structure by taking notes and using the textbook ANNOUNCEMENT: Science club is meeting Tuesday, 1/21

2. Notes and Textbook Today you will be taking notes using the notes pages you printed. You will also use our textbooks to answer questions with your partner Please QUICKLY get one textbook per table

3. DNA and Genes (Chapter 11)

4.  History of DNA 1800’s Mendel determined that offspring inherited traits from parents 1944 Biomolecule that was involved with heredity was DNA (originally proteins were thought to pass on traits because DNA was too simple)

5. Rosalind Franklin and Maurice Wilkins took diffracted photographs of DNA X-rays were passed through DNA crystals, the X-rays were bent by the atoms in the DNA molecule producing an image of the shape

6. 1953 Watson & Crick developed a model of DNA using the diffraction photographs Double Helix = DNA comes in 2 long strands that wrap around each other, “spiral staircase”

7. Turn to page 283 Look at figure 11.2 (don’t forget to read the caption!) Answer the following question and be ready to share with the class! 1. what is another analogy used for the shape of DNA (besides a spiral staircase)

8.  Why is DNA so important? DNA is known as “blueprint of life” DNA contains instructions for making proteins within the cell Genes are on our chromosomes, chromosomes are made of DNA

9. Turn to page 281 Read the paragraph with the heading What is DNA? Answer the following question and be ready to share! Answer the following question and be ready to share! 2. List 3 places in your body that contain proteins 3. Enzymes are a type of protein. Why do we need them?

10. http://learn.genetics.utah.edu/content/begi n/tour/

11. Why is DNA so important? Important for all life on Earth, makes each individual plant or animal unique Helps us understand diseases better & find potential cures Better food crops

12.  DNA Nucleotides DNA is a nucleic acid made from subunits called nucleotides Nucleotide = 3 parts: five-carbon sugar, phosphate group, nitrogenous base –Deoxyribose = the sugar in a DNA nucleotide

13.  How the Double Helix stays together Double Helix has two strands that twist together One strand of DNA is like one half of a zipper – –The backbone of the molecule is alternating phosphates and deoxyribose sugar – –The teeth are nitrogenous bases phosphates deoxyribose bases

14. One strand of DNA (half of a zipper) is a polymer of nucleotides One strand of DNA has millions of nucleotides

15.  Nitrogenous Bases DNA has four different bases CytosineC ThymineT AdenineA GuanineG

16. 2 kinds of Nitrogenous Bases Purines = double ring bases, A and G Pyrimidines = single ring bases, T and C

17.  Complementary Bases Nitrogenous bases on the 2 strands of DNA pair up with one another Cytosine pairs with Guanine with 3 (triple) Hydrogen Bonds Adenine pairs with Thymine with 2 (double) Hydrogen Bonds

18. Turn to page 283 Read the Problem-Solving Lab 11.1 #4, 5, 6: Answer the 3 “thinking critically” questions. You have 5 minutes

19.  DNA Model