1. Chapter 5 5.5 Pg. 86-89 Objective: I can identify and describe the different parts of DNA and use them to explain how genes encode for our traits by dictating how proteins are made.

2.  Store/Transmit Hereditary Information (genes)  Genes: unit of inheritance (1 gene = 1 polypetide)  Two types: DNA, RNA  DNA inherited from parents  Info that programs cells  Transmits info to RNA  Specifically, mRNA  mRNA directs protein synthesis  DNA  RNA  protein

3.  Because N.A. are M.M., they are also polymers  Monomer = nucleotide (3 parts)  5-carbon Sugar = pentose  Phosphate Group  Nitrogenous Base  Polymer = polynucleotide chain  Elements: C, H, O, N, P

4.  There are 5 types of nitrogenous bases (divided into 2 categories)  Pyrimidines (1 ring)  Cytosine (C)  Thymine (T)  Uracil (U)  Purines (2 rings)  Adenine (A)  Guanine (G)  5 N-Bases  5 types of nucleotides

5.  Each of the 5 carbons is numbered:  1’ bonds with N-base of same nucleotide  5’ bonds with phosphate group of same nucleotide ▪5’ carbon is “hanging off” the ring  3’ bonds with phosphate group of NEXT nucleotide 5’ 4’ 3’2’ 1’

6.  Take OH from Sugar and…  H from Phosphate group   Dehydration Synthesis  Breakdown = hydrolysis  Bond = phosphodiester bond  Sugar-Phosphate backbone  Nucleoside = portion WITHOUT phosphate group  Sugar + N-Base OH H

7.  DNA made of two strands  Strands hold together by base pairing  Adenine (A) pairs with Thymine (T)  Cytosine (C) pairs with Guanine (G)  Two strands twist into a spiral shape called  Double Helix complementary

8.  Pentose Sugar  RNA has ribose (4 carbons have –OH)  DNA has deoxyribose (3 carbons have –OH) (1 carbon lost oxygen)  Nitrogenous base  DNA has thymine  RNA has uracil  Single vs. Double Strand

9.  5’ end is the phosphate side of nucleotide  3’ end is the sugar side of nucleotide 5’ 3’ 5’ 3’ 5’ 3’ 5’

10.  Two strands of DNA run anti-parallel to each other: opposite directions  5’ to 3’ & 3’ to 5’  Nucleotide cannot “flip” due to 3D structure - can only “turn” upside down

12.  How? 5 types of nucleotides (nitrogen base)  Sequence of nucleotides encodes information (like letter making words)  AGTACG  one type of polypeptide  GCGGAT  another type of polypeptide ACCGTAGATAGCC  another polypeptide TGGCATCTATCGG (complementary)  1 gene = thousands of nucleotides long

13.  Rosalind Franklin – X-ray diffraction  James Watson and Francis Crick  Put it all together