2. o DNA very large molecule “polymer” o DNA made of repeating subunits called? o Nucleotides o Nucleotides have three parts o Sugar o Phosphate group o Nitrogenous base o Simple sugar in DNA is called? o Deoxyribose o Phosphate group – (sketch it p. 282) o composed of 1 P (Phosphorous) surrounded by 4 O (oxygen) o Nitrogenous base – Carbon (C) that contains 1 or more N (Nitrogen)

3. o What are the names of the 4 Nitrogenous Bases ? o Guanine (G) o Thymine (T) o Adenine (A) o Cytosine (C) o Sketch each nitrogenous base (p. 282 /Honors p. 198) o Nucleotides join together to form long chains o Phosphate group – Deoxyribose (sugar) – Nitrogenous base o Phosphorous & Deoxyribose form the “BACKBONE” of DNA o Nitrogenous bases stick out like teeth of a “zipper” o Adenine = Thymine “always” o Guanine = Cytosine “always” o Purines: Adenine & Guanine (double rings of carbon) o Pryimidines: Thymine & Cytosine (single ring of carbon)

4. o Use the textbook illustration (p. 282/ Honors p. 198) o The paper should be held horizontally o Count & Collect the # of pentagons, hexagons, & elements needed to make the nitrogen bases o BE sure to attach the elements (O, C, H, & P) to the correct position on the compounds o Include the double bonds & make sure to put elements in the appropriate position o Glue the titles Purines & Prymidines on to your paper o Classify the nitrogen bases in a group with either Purines & Prymidines o Make each of the nitrogen bases with your supplies o Glue the nitrogen base TITLES above each of the appropriate nitrogen bases: adenine, guanine, thymine, & cytosine o Create a NUCLEOTIDE: illustrate a phosphate group & deoxyribose (pentagon) & attach it to ONE of the NITROGEN BASES to the sugar (p.282 / 197) o Label the phosphate, deoxyribose, & the nitrogen base in the nucleotide