Macromolecules Building Complex Molecules That Comprise Living Things

Comparison of Terms Molecule Two or more atoms joined by chemical bonds Macromolecule Large polymer made of repeating monomer units Four types of organic macromolecules are important in living systems.

Macromolecules: Polymers Made of Repeating Monomers Macromolecule Monomer Unit CarbohydratesSugars Lipids Fatty acids Proteins Amino acids Nucleic Acids Nucleotides

Organic Macromolecules Contain Carbon  Question: How many electrons does carbon need to fill its outer energy level?

Carbon atoms can be joined by single, double or triple bonds. double bond triple bond

Synthesis and Breakdown of Macromolecules Dehydration Synthesis Removal of water to add monomer units Hydrolysis Addition of OH and H groups of water to break a bond between monomers

Dehydration Synthesis / Hydrolysis Dehydration Synthesis Hydrolysis

Carbohydrates: Structure SimpleSimple –Monosaccharides= one sugar unit Glucose = blood sugar All cells use glucose for energy

Chemical Formula for a Six-Carbon Sugar

Carbohydrates: Structure HOH CH 2 OH H HO H OH H HO HH O O HOCH 2 H CH 2 OH HHO HHO O H HO H OH H HO H OH H O Glucose O HOCH 2 H CH 2 OH HHO HO HHO Fructose Sucrose & Water ++ SimpleSimple –Disaccharides = two sugar units

Carbohydrates: Structure SimpleSimple –Disaccharides = two sugar units Sucrose = glucose + fructose table sugarSucrose = glucose + fructose table sugar Lactose = glucose + galactose milk sugarLactose = glucose + galactose milk sugar Maltose = glucose + glucose seed sugarMaltose = glucose + glucose seed sugar

Carbohydrates: Structure ComplexComplex –Polysaccharides= many sugar units Starch -- storage in plantsStarch -- storage in plants Glycogen -- storage in animalsGlycogen -- storage in animals Cellulose -- plant cell walls, indigestible (fiber)Cellulose -- plant cell walls, indigestible (fiber)

Carbohydrates: Functions Energy sourceEnergy source Structural componentStructural component Cell-cell communicationCell-cell communication

Mac ‘n Cheese Nutrition Label Start here Serving Size 1 cup (228g) Servings Per Container 2 Amount Per Serving Calories 250 Total Fat 12g Cholesterol 30mg Sodium 470mg20% Total Carbohydrate 31g Vitamin A Protein 5g 4% Vitamin C2% Calcium20% Iron4% 10% Saturated Fat 3g Trans Fat 1.5g 15% Dietary Fiber 0g Sugars 5g 0% 18% Nutrition Facts Get enough of these nutrients Limit these nutrients % Daily Value Calories from Fat 110

Lipids: Structure Triglyceride— predominant form in dietTriglyceride— predominant form in diet –One molecule of glycerol –Three fatty acids

Lipids: Structure Types of Fatty AcidsTypes of Fatty Acids –Saturated – 2H per internal carbon –Unsaturated -- <2H per internal carbon  one or more double bonds Monounsaturated – one double bondMonounsaturated – one double bond Polyunsaturated – more than one double bondPolyunsaturated – more than one double bond

HH C H C H OH C H C O C C C H H H H H H H C C H H H H H H H C C O C O C C C H H H H H H H Triglyceride Triglyceride Formation C OH C C C O H H H H H H H Add 3 Fatty Acids Glycerol HOH 3 Waters C OH C C C O H H H H H H H C C C C O H H H H H H H O C H C H C H OO HH Remove These Waters C O C C C H H H H H H H C C H H H H H H H C C O C O C C C H H H H H H H

Emulsification Physical dispersion of lipidsPhysical dispersion of lipids –Mixing with a molecule having a polar and non-polar end –Bile from gall bladder emulsifies fats prior to digestion

Lipids: Structure Polar Head Glycerol Fatty Acid Tails HydrophobicHydrophilic Phospholipid— component of cell membranesPhospholipid— component of cell membranes

SteroidsSteroids –Linked carbon rings –Natural body components HormonesHormones CholesterolCholesterol Lipids: Structure

Steroids Cholesterol Estradiol Testosterone

Lipids: Functions Concentrated energy sourceConcentrated energy source Structural components of cell membranesStructural components of cell membranes –Phospholipids –Cholesterol CommunicationCommunication –Steroid Hormones Protection from waterProtection from water –Waxes Cholesterol Phospholipids

Mac ‘n Cheese Nutrition Label Start here Serving Size 1 cup (228g) Servings Per Container 2 Amount Per Serving Calories 250 Total Fat 12g Cholesterol 30mg Sodium 470mg20% Total Carbohydrate 31g Vitamin A Protein 5g 4% Vitamin C2% Calcium20% Iron4% 10% Saturated Fat 3g Trans Fat 1.5g 15% Dietary Fiber 0g Sugars 5g 0% 18% Nutrition Facts Get enough of these nutrients Limit these nutrients % Daily Value Calories from Fat 110

Proteins: Structure Amino Group Amino Group The “R” Group Differs for Each Amino Acid Carboxylic Acid Group Central Carbon R Primary structure = chain of amino acidsPrimary structure = chain of amino acids –Amino acids have common features

Proteins: Structure Forming the Protein Chain Dehydration Synthesis between COOH & NH 2 Phenylalanine Leucine

Proteins: Structure Forming the Protein Chain WaterWater The Peptide Bond Phenylalanine-Leucine Dipeptide

Four Levels of Protein Structure Primary (Sequence) Secondary (Coiling by Hydrogen Bonding) Tertiary (Folding by R-group interactions) Quaternary (Two or more chains associating)

Four Levels of Protein Structure Primary Structure = sequence of amino acids in chain

Four Levels of Protein Structure Secondary StructureSecondary Structure Folded structure due to hydrogen bonds between the amino and acid groups of amino acids Folded structure due to hydrogen bonds between the amino and acid groups of amino acids C O N H C O N H C O N H C O N H or

Found in most proteins Found in silk

Four Levels of Protein Structure Tertiary Structure:Tertiary Structure: Three dimensional folded structure due to attractions and repulsions between R groups Three dimensional folded structure due to attractions and repulsions between R groups Can involve covalent bonding hydrogen bonding ionic interactions hydrophilic and hydrophobic interactions

Hair Curling |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| Straight Hair |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| |S|S||S|S||S|S||S|S| Naturally Curly Hair

Four Levels of Protein Structure Quaternary Structure:Quaternary Structure: Association of two or more protein chains Association of two or more protein chains eg. Hemoglobin is composed of 4 protein chains eg. Hemoglobin is composed of 4 protein chains 2 are called alpha hemoglobin 2 are called alpha hemoglobin 2 are called beta hemoglobin 2 are called beta hemoglobin

Denaturation of Proteins Disruption of secondary, tertiary or quaternary protein structureDisruption of secondary, tertiary or quaternary protein structure Caused by heat or changes in pHCaused by heat or changes in pH Irreversible, causes loss of protein functionIrreversible, causes loss of protein function protein unfolds

Proteins: Functions Structural Component of CellsStructural Component of Cells Control of Metabolic Reactions: enzymesControl of Metabolic Reactions: enzymes Maintain homeostasisMaintain homeostasis –Transport substances in blood –Antibodies protect against invaders Growth and RepairGrowth and Repair Support and MotionSupport and Motion CommunicationCommunication –Protein Hormones –Cell Receptors Energy sourceEnergy source Protein