lOMoARcPSD 34747998 Scan to open on Studocu Scan to open on Studocu MCB450 Exam 1 Study Guide MCB450 Exam 1 Study Guide Introductory Biochemistry University of Illinois at Urbana Champaign Introductory Biochemistry University of Illinois at Urbana Champaign Studocu is not sponsored or endorsed by any college or university Studocu is not sponsored or endorsed by any college or university Downloaded by Lusa Bear lusabear58 gmail com lOMoARcPSD 34747998 Lecture One Water Non Covalent Intermolecular Interactions H bonds Ionization of Weak Acids Bases Titrations pH LO1 Know the four types of biological molecules their general roles in cells The four classes of Biological Molecules Proteins Nucleic Acids DNA RNA Carbohydrates poly and oligosaccharides Lipids Fatty Acids PROTEINS Structure Highly versatile Regulation Catalysis Signaling Transport Transcription factors Iron amino acid glucose Hormones transcription factors growth factors Enzymes Actine myosin tubulin Collagen of tendons Cartilage Elastin of ligaments Keratin of hair feathers and nails Fibroin of silk and webs Peptide Bonds Condensation Rxn AMINO ACIDS are the building blocks of protein NUCLEIC ACIDS Information molecules in the cell Monomer 3 part molecule Phosphate group Sugar Base All put together called a NUCLEOTIDE DNA deoxyribonucleic acid Double helix made of 2 strands Polymers of deoxyribonucleotides Strands held together by NON COVALENT INTERACTIONS between bases Base A with Base T Base G with Base C RNA ribonucleic acid Single stranded polymer of ribonucleotides containing bases A G C and U in the place of T Polymers of nucleotides Downloaded by Lusa Bear lusabear58 gmail com lOMoARcPSD 34747998 Nucleotides are joined by PHOSPHODIESTER BONDS Central Dogma of Molecular Biology Information flows from DNA RNA Protein workforce of the cells Help carry genetic information within between the cells CARBOHYDRATES Linear or branched polymers of MONOSACCHARIDES Monosaccharides can be classified according to of carbon atoms Aldoses Ketoses Sugars with ALDEHYDE as their most oxidized functional group Sugars with KETO as their most oxidized functional group Most sugars are in the CYCLIC FORM not in the open chain acrylic form Joined to form disaccharides oligosaccharides and polysaccharides Disaccharides Lactose glucose galactose Sucrose glucose fructose Maltose glucose glucose Polysaccharides Branched glycogen from animals Unbranched cellulose from plants Starch from plants FUNCTION Important fuel source esp glucose Glucose is stored as glycogen in animals starch in plants Structural molecules Cellulose chitin Signaling molecules Lubricants Hyaluronic acid in joints Mucus Cell cell recognition eg blood group antigens LIPIDS Water insoluble molecules that are highly soluble in organic solvents Free fatty acids nonesterified fatty acids Most commonly used as a fuel Downloaded by Lusa Bear lusabear58 gmail com lOMoARcPSD 34747998 Simplest form of lipid Long hydrocarbon chain carboxyl group SATURATED single bond can pack more tightly together at room temperature and makes it a SOLID at room temperature butter Found in most fats UNSATURATED one or more double bonds Create kink in the hydrocarbon tail which results in LOOSER PACKING Liquid at room temperature Found in natural fats Triacylglycerols Storage form of fatty acids esterified Fats Consist of a glycerol and 3 fatty acids Created via 3 condensation reactions creates ESTER LINKAGES that link fatty acid carboxyl groups to the HYDROXYL groups in glycerol Mediated by enzyme ACETYLTRANSFERASE Membrane lipids Phospholipids membrane lipid Glycolipids bound to carbohydrates membrane components Steroids polycyclic hydrocarbons signaling molecule and membrane Cholesterol is a steroid and built from 4 fused hydrocarbon components rings Downloaded by Lusa Bear lusabear58 gmail com lOMoARcPSD 34747998 Hydrocarbon tail is connected to the steroid at one end and hydroxyl group is connected to the other end Lipids serve as a barrier due to its chemical properties Lipids are AMPHIPATHIC dual chemical nature Part of the molecule is hydrophilic Can dissolve in water Other part made up of 1 hydrocarbon chains and is hydrophobic Cannot dissolve in water HYDROPHILIC HEAD is made of choline phosphate and glycerol Phospholipids spontaneously form lipid bilayers due to amphipathic nature of lipid molecules FUNCTIONS OF LIPIDS Major component of membrane phospholipids glycolipids steroids Chemical messengers steroid hormones Long term energy storage fat Protection against heat loss fat insulation Protection against physical shock fat Protection against water loss LO2 Know the properties of the four types of covalent bonds How are they formed What is a condensation reaction COVALENT BONDS Bonds in which the electrons are shared by the participating atoms Downloaded by Lusa Bear lusabear58 gmail com lOMoARcPSD 34747998 PEPTIDE BONDS Each amino acid is attached to another amino acid by a covalent bond Proteins are Linear Polymers of L Amino Acids that are joined by PEPTIDE BONDS Formed through Condensation Reaction H2O eliminated between COOH of one amino acid and NH2 of the next Carboxyl group from one amino PHOSPHODIESTER BONDS A covalent bond in RNA or DNA that holds a polynucleotide chain together by joining a PHOSPHATE GROUP at position 5 in the pentose sugar of one nucleotide to the hydroxyl group at position 3 in the pentose sugar of the next nucleotide Nucleic acids are polymers of nucleotides that are joined by phosphodiester bonds acid interacts with amino group from other amino acid with the REMOVAL of a water molecule Creation of peptide bond is associated with removal of one water molecule Peptide bonds help to hold amino acids together to form polypeptides Mediated by enzyme PEPTIDYL TRANSFERASE Very stable bonds CONDENSATION RXN H20 eliminated between OH of nucleotide and phosphate of next Catalyzed by enzyme DNA or RNA POLYMERASE GLYCOSIDIC BONDS Carbohydrates are made up of monosaccharides linked together into polysaccharide chains by a type of covalent bond known as a glycosidic bond Carbohydrates are linear or branched polymers of monosaccharides Carbohydrates can be linked together in chains and form branches via glycosidic bonds Mediated by enzyme Glycogen or Starch Synthase Downloaded by Lusa Bear lusabear58 gmail com lOMoARcPSD 34747998 ESTER BONDS Triglycerides are lipids consisting of one glycerol molecule bonded with 3 fatty acid molecules The bonds between the molecules