Review from last lecture: 2 in the first circle, 8 in the second and third.IV. Oxygen and nitrogen are electron hogs. They don’t share electrons equally.VI. Hydrogen Bonds: WEAKEST type of bond.Form between polar molecules.Called hydrogen bond because hydrogen has to be involved.Polar Molecules;Contain polar covalent bonds in which there is unequal sharing of electronsPart of the molecule has partial positive or partial negative charge?Hydrogen bond:Weak attraction betweenOpposites attract;- -O – H - - - - O – H (HYDROGEN BOND)| |H H+ +(dashed line because the bond is weak)Covalent Bond:Strength: StrongDescription: A bond in which the sharing of electrons between atoms results in each atom having a maximally filled outermost shell of electronsExample: The bond between hydrogen and oxygen in a molecule of waterIonic Bond:Strength: moderateDescription: The bond between the two oppositely charged ions (atoms or molecules that were formed by the permanent transfer of one or more electrons.)Example: The bond between Na+ and CI- in saltHydrogen bond:Strength: WeakDescription: The bond between oppositely charged regions of molecules that contain covalently bonded hydrogen atomsExample: The bonds between molecules of waterLife depends on WATERWater molecules are polarWater is liquid at body temperatureWater can absorb and hold heat energyWater helps regulate body temperatureWater is a good solvent for other moleculesSolvent: liquid in which other substances dissolveSolute: any dissolved substancesHydrophilic: Polar molecules or ions (charged atoms) are attracted to water and interact easily, therefor will dissolve in water.Hydro means: water. Phillic means: love Phobic means: hate.Hydrophobic: Nonpolar/neutral molecules do not interact with water and therefor cannot dissolve in water.Example: OilThe Organic Molecules of Living OrganismsCarbon is the building block of living thingsComprises 18% of the body by weight (but only 0.03% of Earth’s crust)Forms four covalent bondsCan form single or double bondsCan build micro- or macromoleculesFatty acidNon polar covalent bonds ^^Fatty acid= non polar moleculeThe Organic Molecules of Living Organisms4 Classes of organic molecules:1. Carbohydrates2. Lipids3. Proteins4. Nucleic AcidsAnother critically important molecule: ATPMacromolecules Are Synthesized and Broken Down within the CellThe larger organic molecules (“macromolecules”) are made of chains of small subunits held together by chemical bondsE.g., Carbohydrates are chains of monosaccharides (simple sugars); proteins are chains of amino acidsWe consume macromolecules in our diets, break them down in digestion, and then we may rebuild new, useful molecules from the subunitsDehydration Synthesis: (a.k.a. “Condensation”)Builds macromolecules from smaller subunitsRemoves equivalent of a water molecule to link molecular subunitsRequires energyOpposite ^Hydro=waterHydrolysisBreaks apart a macromolecule into its subunitsAdds the equivalent of a water molecule to break apart macromoleculesReleases energyDehydration synthesis is the reverse of hydrolysisA simple Protein (Polypeptide) is synthesized by linking Amino Acids in Dehydration ReactionsIf you consume a carbohydrate and break down the molecule in digestion, which of the following would NOT be true?Water would be release.Adds the equivalent of a water molecule to break apart macromoleculesCarbohydratesCarbohydrates are macromolecules made of Monosaccharide subunitsGeneral formula: Cn(H20)nExamples of Monosaccharides (simple sugars):Glucose (C6H12O6)FructoseGalactoseRiboseDeoxyriboseMonosaccharides can be linked together via dehydration synthesisDisaccharides = two Monosaccharides linked togetherSucrose = glucose + fructoseMaltose = glucose + glucoseLactose = glucose + galactosePolysaccharides (or “Complex Carbohydrates) = thousands of Monosaccharides joined in chains and branchesStarch: made in plants; stores energyGlycogen: made in animals; stores energyCellulose: indigestible polysaccharide made in plants for structural support (cockroaches)Chitin: found in the exoskeletons of insects and crustaceans for structural supportMushrooms, ticks, lobster. (not squashable.)LipidsLipids are composed of mainly carbons and hydrogensCarbon and Hydrogen form nonpolar covalent bondsTherefore Lipids are (mostly) nonpolar and hydrophobic (can’t dissolve in water)Three important classes of lipids:Triglycerides: energy storage moleculesPhospholipids: cell membrane structureSteroids: many important hormones are steroids (e.g., estrogen and testosterone)CarbsSubunits (monomersFunctionsExamplesMonosaccharaidesEnergy structureNon polar molecules don’t dissolve in polar substances such as water.Lipids: TriglyceridesAlso known as fats and oils*Composed of glycerol and three fatty acidsFatty acids are long chains of carbons and hydrogensSaturated (in fats)—has only single covalent bonds, solid at room temperatureUnsaturated (in oils)—contains one or more double covalent bond, liquid at room temperatureStored in adipose tissueEnergy storage moleculesFatty acid with saturated fatty Triglycerides withAcids have straight tails, allowing them unsaturated fatty acids haveTo pack closely together. kinked tails, preventingThem from packing closelytogether.Lipids: PhospholipidsStructure:Glycerol + two fatty acids + phosphate groupOne end of molecule—the phosphate “head”—is water soluble (hydrophilic)Other end of molecule—the fatty acid “tails”—is water insoluble (hydrophobic)Function:Primary component of cell membranesIn water, Phospholipids form a bilayer that acts as a barrier around a cellBIOL 1140 1st Edition Lecture 3 Outline of Last Lecture I. Covalent Bondsa. Protons, electrons, balancing them b. AtomsII. Atomic numbersa. examplesOutline of Current Lecture I. Bondsa. Hydrogen bonds, polar molecules, covalent bonds, ionic bondII. Carbohydratesa. Starch, glycogen, celluloseIII. Lipidsa. Triglycerides, phospholipidsReview from last lecture: 2 in the first circle, 8 in the second and third. IV. Oxygen and nitrogen are electron hogs. They don’t share electrons equally. V.VI. Hydrogen Bonds: WEAKEST type of bond. 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.- Form between polar molecules. - Called hydrogen bond because hydrogen has to be involved.- Polar Molecules;o Contain polar covalent bonds in which there