Macromolecules final

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CHAPTER 5 The Structure and Function of Macromolecules “You are what you eat!”
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  • 1. CHAPTER 5The Structure and Function ofMacromoleculesYou are what you eat!

2. - Anorexia andbulimia are major eating disorderssuffered in theworld 3. Iron deficiencyNormal RBCs 4. Goiter: Iodine DeficiencyThyroid Enlargement 5. Rickets: vitamin D deficiency 6. Bodybuilding 7. What does it mean to be aMACROmolecule? You must be a Large molecule You have a complex structure Macromoleculelittle molecule 8. I. Most macromolecules are polymers, built from monomers What is a polymer? Poly = many; mer = part. A long molecule made of monomers bondedtogether What is a monomer? A monomer is a sub-unit of a polymer. 9. Three of the classes of lifes organic molecules arepolymers Carbohydrates, Proteins, Nucleic acids 10. A. Making and Breaking Polymers How do monomers bind to form polymers? condensation reactions called dehydration synthesis (removal of water) 11. How can polymers break down when monomers are needed? Hydrolysis reaction Hydro = water; lysis = break Water is added and the lysis of the polymer occurs. 12. Hydrolysis 13. II. Classes of Organic Molecules: Carbohydrates Lipids Proteins Nucleic Acids 14. A. CARBOHYDRATES 15. What are Carbohydrates? Sugars and their polymers Carbo = carbon, hydrate = water; carbohydrates have the molecular formula (CH2O)n Functions of Carbohydrates in living things: Major fuel/energy source Can be used as raw materials for other Macromolecules Complex sugars = building material in plants What is the Carbohydrate Monomer? Monosaccharide (mono = one; saccharide =sugar) 16. 1. Structure of Monosaccharides Contain only C, H, O Hydroxyl group is attached to each carbon One carbon contains a carbonyl group 17. Classified according to the size of their carbon chains andlocation of Carbonyl group 18. In aqueous solutions many monosaccharides formrings: 19. 2. Structure of Disaccharides Consist of two monosaccharides Are joined by a glycosidic linkage What reaction forms the glycosidic linkage? Dehydration synthesis 20. 3. Polysaccharides Structure: Polymers of a few hundred or a fewthousand monosaccharides. Functions: energy storage molecules or forstructural support: 21. Starch is a plant storage form of energy, easilyhydrolyzed to glucose units 22. Cellulose is a fiber-like structural material made ofglucose monomers used in plant cell walls 23. Why is Cellulose so strong? Glucose monomers are flipped to expose equal Hydroxylgroups on either side of the chain When Cellulose chains are lined up next to each other, theyHydrogen Bond making a strong material thats difficult tobreak! 24. Glycogen is the animal short-term storage formof energy Glucose monomers 25. Chitin is a polysaccharide used as a structuralmaterial in arthropod exoskeleton and fungal cellwalls. 26. B. LIPIDS What are Lipids? Fats, phospholipids, steroids, waxes, pigments Hydrophobic (hydro=water; phobic = fearing) Consist mostly of hydrocarbons Do NOT consist of polymers 27. Functions of Lipids in living things: Energy storage membrane structure Protecting against desiccation (drying out). Insulating against cold. Absorbing shocks. Regulating cell activities by hormone actions. 28. 1. Structure of Fats (Triglycerides) Consist of a single glycerol and usually three fattyacids Glycerol an alcohol with three carbons Fatty Acid - Long Hydrocarbon chains with aCarboxyl group at one end. 29. Saturated and Unsaturated Fats Unsaturated fats : one or more double bonds between carbons in the fatty Oleic acid acids allows for kinks in the tails liquid at room tempcis double bond (b) Unsaturated fat and fatty acid causes bending most plant fats Saturated fats: No double bonds in fatty acid tails solid at room temp most animal fatsStearic acid (a) Saturated fat and fatty acid 30. Saturated fatty acid 31. Saturated fattyacid Unsaturatedfatty acidWhy are Unsaturated Fats better foryou than Saturated Fats? 32. 3. Phospholipids Structure: Glycerol + 2 fatty acids + phosphategroup. Function: Main structural component ofmembranes, where they arrange in bilayers. 33. Phospholipids in Water 34. 4. Waxes Function: Lipids that serve as coatings for plant parts and as animal coverings. 35. 5. Steroids Structure: Four carbon rings with no fatty acid tails Functions: Component of animal cell membranes (Ex: Cholesterol) Modified to form sex hormones 36. PROTEINS 37. C. Proteins What are Proteins? Chains of amino acid monomers connected bypeptide bonds Have a 3 dimensional globular shape 38. Examples of Protein Functions Immune System Binding of antibodies (proteins) to foreign substances Transport Membrane transport proteins that move substances across cell membranes Hemoglobin carries oxygen, iron, and other substances through the body. Muscle Contraction actin and myosin fibers that interact in muscle tissue. Signaling Hormones such as insulin regulate sugar levels in blood. 39. Amino Acids Monomers of polypeptides Molecules with carboxyl and amino groups Differ in their properties due to differing sidechains, called R groups 40. 20 differentaminoacids existThe sequence ofamino acids and theinteractions of thedifferent amino acidsdetermine a proteinsshape 41. Peptide bonds connect amino acids to formpolypeptide chains One or more polypeptide chains make up aprotein 42. Proteins are very complex! Their specificstructure determines their function.HEMOGLOBIN: Transport of ACTIN: Filament involved ingases and iron in blood muscle contraction 43. Four Levels of Protein Structure Primary structureHN +3Gly ProThr GlyGlu Thr Gly Amino acidAmino endCys LysSeusubunits Is the unique sequence ofLeuProMetValLysValamino acids in aLeu AspAlaVal Arg GlySerProAlapolypeptide Glu LleAsp Thr Lys SerLys Trp TyrLeu Ala Gly lle SerProPheHisGlu HisAla Glu Val Ala Thr PheValAsn lle ThrAspTyr AlaArgSerArgAla GlyPro LeuLeuSer ProSerTyrTyrThr SerThr AlaVal oVal ThrAsnProLysGlu coFigure 5.20Carboxyl end 44. Secondary structure Is the folding or coiling of the polypeptide into a repeating configuration resulting from hydrogen bonding of amino with carboxyl groups Includes the helix and the pleated sheet pleated sheetO HO HOO HHH H HHRAmino acidC C N R C C N RC C NC C N N N C N subunitsC N R CCRC C R CR C C HOH O H OH O H HHR RR R OOCO C O C CHHHH C N C N H C NC NH C N C N H C N C NH HH HC H OCHO C H O C HO C RR RRRC H C H N HO CN HO CN O CH O CN H helixC H C R HR H C R H C RN H O CN HO C O CN H O CNCC HRR HHFigure 5.20 45. Tertiary structure Is the overall three-dimensional shape of a polypeptide Results from interactions between amino acids and R groupsHydrophobicinteractions andCHCHvan der WaalsCH22H3C CH3 interactionsO Hydrogen H H3C CH3 Polypeptide bond O CH backboneHO CCH2CH2 S S CH2Disulfide bridgeO CH2 NH3+ -O C CH2 Ionic bond 46. Quaternary structure Is the overall protein structure that results from theaggregation of two or more polypeptide subunits 47. Chaperonins Are protein molecules that assist in the properfolding of other proteinsCorrectlyfolded Polypeptideprotein CapHollowcylinder ChaperoninSteps of Chaperonin 2 The cap attaches, causing the The cap comes3 (fully assembled) Action:cylinder to change shape in off, and the properly 1 An unfolded poly-such a way that it creates afolded protein is peptide enters the hydrophilic environment for the released. Figure 5.23 cylinder from one end. folding of the polypeptide. 48. Sickle Cell Disease: A simple change in Primary Structure 49. Enzymes Are a type of protein that acts as a catalyst, speedingup chemical reactions up to 10 billion times fasterthan they would spontaneously occur. 50. Environmental Factors That DetermineProtein Conformation Change in environment may lead to denaturationof protein (pH, temperature, salinity, etc.) Denatured protein is biologically inactive Can renature if primary structure is not lost 51. NUCLEIC ACIDS 52. D. Nucleic Acids : The stuff ofGenes Nucleic acids store and transmit hereditary information Genes Are the units of inheritance Program the amino acid sequence of polypeptides Are made of nucleic acids 53. Two Kinds of Nucleic Acids DNA (Deoxyribonucleic acid) double stranded can self replicate makes up genes which code for proteins is passed from one generation to another RNA (Ribonucleic acid) single stranded functions in actual synthesis of proteins coded for by DNA is made from the DNA template molecule 54. 1. Nucleotide Monomer Structure Both DNA and RNA are composed of nucleotidemonomers. Nucleotide = 5 carbon sugar, phosphate, andnitrogenous baseDeoxyribose in DNARibose in RNA 55. 2. Building the Polymer Phosphate group of one nucleotide forms strongcovalent bond with the #3 carbon of the sugar ofthe other nucleotide. 56. DNA: Double helix 2 polynucleotide chains woundinto the double helix Base pairing between chainswith H bondsA-TC-G 57. Summary of the OrganicMolecules: