BIOL 120 1st Edition Lecture 6 Outline of Last Lecture II Macromolecules a monomer polymer dehydration reaction hydrolysis III Carbohydrates a monosaccharides polysaccharides Aldose ketose Glycosidic linkage glycogen cellulose starch Chitin Peptidoglycan glycoproteins Outline of Current Lecture I Nucleic Acids Nucleotides a Nucleotides nucleic acid purines pyrimidines phosphorylation II Structure of DNA III Structure of RNA IV Lipids beginning a Lipids saturated unsaturated monounsaturated polyunsaturated Current Lecture I Nucleic Acids Nucleotides A Nucleotides consist of a pentose sugar 5 carbon phosphate group bonds to C5 and a nitrogen containing base bonds to C1 1 Ribonucleotides polymerize to form RNA 2 Deoxyribonucleotides polymerize to form DNA 3 Connect to for polymers through a phosphodiester bond phosphate is connected at C5 of pentose sugar These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute B Nucleic Acid a polymer of bonded nucleotides that go through a condensation reaction 1 two types of nitrogenous bases a Purines double ring structure Adenine Guanine b Pyrimidines single ring structure Thymine only in DNA Cytosine Uracil only in RNA 2 C Polymerization 1 Polymerization of nucleic Acids is an endergonic process add in energy energy comes from phosphorylation of nucleotides i In the polymerization of nucleic acid 2 phosphates are transferred creating a nucleoside triphosphate a Phosphorylation the transfer of one or more phosphate groups to a substrate molecule raising potential energy enables endergonic reactions i i e AMP ADP ATP II Structure of DNA A primary structure consist of a sequence of nitrogen containing basis ATGC B Secondary structure consist of 2 DNA strands running in opposite directions 1 i e 3 prime top of 1 connects to 5 prime top of 2 and 5 prime bottom of 1 connects to 3 prime bottom of 2 2 Held together by complimentary base pairs twisted into a double helix a A T C G amount of A T and amount of C G b total number of purines and pyrimidines is equal 3 DNA can store and duplicate the information needed to grow and reproduce C The sugar phosphate in both DNA and RNA is directional 1 one end of the strand has an unlinked 5 C and the other end is an unlinked 3 C a written from 5 3 D What Watson and Crick discovered 1 DNA strands run in opposite directions of each other 2 Sugar phosphate back bones are hydrophilic and face the exterior of the structure 3 Nitrogenous base pairs face interior hydrophobic 4 Purines always pair with pyrimidines and not with themselves and vice versa a A T has a two hydrogen bond b C G has a three hydrogen bond 5 DNA has different size grooves a major and minor 6 DNA can store and transmit biological information E III Structure of RNA A Same components as DNA sugar phosphate backbone 4 types of nitrogenous bases pentose sugar B Differs from DNA in 3 ways 1 Contains Uracil instead of Thymine 2 Single stranded 3 Contains ribose instead of deoxyribose i presence of the OH group makes RNA much more reactive and less stable than DNA C Secondary Structure 1 Results from complementary base pairing A U G C D RNA is responsible for functions within cell 1 transcription replication translation E Like DNA 1 can function as information containing molecule and can self replicate 2 Can function as a catalytic molecule ribozymes are enzyme like RNAs IV Lipids A Lipids loosely defined group of molecules with one main chemical characteristic insoluble in water a examples fats oils waxes steroids Etc 1 Hydrophobic due to high proportion of nonpolar C H bonds B Made from 2 main molecules 1 Fatty Acids a long chain hydrocarbons with COOH at one end i Saturated no double bond between carbon atoms high melting point animal origin i e butter ii Unsaturated 1 or more double bonds low melting point plant origin i e olive oil iii Monounsaturated fatty acid with one double bond iv Polyunsaturated fatty acid with more than one double bond v Trans fat fats produced industrially 2 Gycerol a 3 carbon polyalcohol 3 OH groups b Triglycerides or triacylglycerol i many lipid molecules consist of a glycerol with 3 fatty acids attach one to each carbon of glycerol backbone a fatty acids can be different from each other most common are 14 to 20 carbons C the C H bond provides stores more energy than carbs or glucose