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Nucleic Acids Components (Nitrogen) Bases Purines Adanine Guanine Double Ring Pyramidines Cytosine Uracil Thymine Single Ring Made from rings of Carbon and Nitrogen Bases Pair through hydrogen bonds A complementary with T (double bond) G complementary with C (triple bond) bases changed together through pentose sugar ribose with oxygen deoxyribose with out oxygen Base + a Sugar = Nucleoside e.g. adenosine throw in 3 phosphor = ATP (aka the universal high energy carrier) as in cAMP second messenger eg. guaninosine as in GTP used in proten synthesis carbohydrate metabolims secondary messengers eg. cytosinosine as in CTP Base + Sugar + Phosophor = Nucleotide polynucleotides = multiple Nucleotides = DNA or RNA phosphor can link to sugars to each other allowing for these nucleotide chains Nucleotides are acids AMP, TMP, UMP, GMP = RNA acid composition dAMP, dTMP, dCMP, dGMP = DNA acid composition RNA Bases Used A, G, U, C Definition differences between DNA and RNA Double vs Single Stranded T vs U dR vs R sugar chains of nucleoside 5' monophosphates joined via 3'5' phosphodiester bonds strands bound through hydrogen bonds to form the double helix are anti-parallel (5'->3' on side, 3' ->5' on other side) DNA Bases Used A, G, T, C Strands of DNA held together by hydrogen bonds between bases Genetic information stored as sequence of basis along chain DNA sequences only code how to make proteins proteins are amino acids chained together 3 bases together code an amino acid = codon introns - that do not contain info exons - contain info for an acid 64 total present in DNA (in any organism) 61 Amino acids 3 Stop codes degenerate - several codes for same amino acid possible a sequence of codons to produce a protein is a gene gene expression - process of creating the protein 6.4 x 109 base pairs 20 - 30 thousand genes DNA is folded into certain structures (p. 182) chromatin DNA + Proteins (histones) 5 types of histones H1, H2a, H2b, H3, H4 general mess of DNA when not organized in to chromosomes nucleosome core of 4 histones + DNA wrapped around this core nucleofilament H1's used to create tighter packing together of nucleosomes nucleofilaments are then coiled/twisted chromosomes chromatin sections organized in to recognizable arangements 46 total = 23 pairs only present during cell division DNA Replication process of making copies of DNA each strand is copied separately = semi-conservatively ie. unzipped and each side copied 1. DNA aProtein melts the DNA (splits the hydrogen bonds) at origin of replication - start of copy alone requires ATP 2. DNA Helicase continues break/melt of DNA requires ATP 3. SSBP Single Stranded Binding Proteins Prevents DNA strands from reconnecting during replication covers/binds to open strands 4. Primase (RNA Polymerase) places section of RNA on to open strand RNA primer needed before DNA can be made 5. DNA Polymerase III Creates the complimentary strand of DNA, ie. performs the copy DNA after primer 6. DNA Polymerase I removes RNA primers and replaces it with DNA

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