3Section 1: Atoms, Elements, & Compounds (p Section 1: Atoms, Elements, & Compounds (p ) Section 2: Chemical Reactions (p ) Section 3: Water & Solutions (p ) Section 4: The Building Blocks of Life (p )
4Atoms, Elements, and Compounds Section 1Atoms, Elements, and Compounds
5Objectives Living things consist of atoms of different elements Ions form when atoms gain or lose electronsAtoms share pairs of electrons in covalent bonds
6The atom The atom is the smallest basic unit of matter Atoms are very smallSmallest components of an element that retains its propertiesElements are made of countless atoms of the elementEach atom has the same properties as the elementAtoms have a nucleusNeutrons that are neutral & Protons that are positive are in the nucleusElectrons that are negative orbit around the nucleus
7The atom There are three parts of a an atom Subatomic particle Charge LocationProtonPositiveNucleusNeutronNeutralElectronNegativeSurrounding nucleusProtons are positively charged and found in the nucleusNeutrons have no charge; they are neutral; They are found in the nucleus as wellElectrons are negatively charged and orbit around the nucleusThe atomic # identifies the element; Tells you the amount of protonsProtons tells you the amount of electrons. They are oppositely charged and need to “cancel” eachother outAtomic mass tells you the average amount of protons and neutrons in the nucleusSo to find neutrons, subtract the atomic # (amount of protons) from the atomic mass
8ElementsAn element is one particular type of atom, and it cannot be broken down into a simpler substance by ordinary chemical meansGoldAluminumHeliumGive a brief overview of the periodic tableShow the noble gases, and what makes them so nobleShow metals & nonmetals
10Key Elements CHOPSN In biology, there are SIX very important elements CarbonHydrogenOxygenPhosphorusSulfurNitrogenCHOPSNHydrogen (59%), Oxygen (24%), Carbon (11%), Nitrogen (4%), make up 80% of the components of the cellThese make up biomoleculesCarbon is very important b/c we are CARBON-BASED lifeformsCarbon also acts as a “building block”Organic chemistry is the chemistry of carbon-carbon bonds
11How are elements different The number of protons determines the identity of an elementCarbon: 6 protonsOxygen: 8 protonsThe number of electrons determines the property of an elementCarbon: 6 electrons, 4 on OUTSIDEOxygen: 8 electrons, 6 on OUTSIDERemember the # of protons, AKA the atomic #, identifies the elementGo over energy levels (2 electrons in the first level, 8 electrons in the second, 8 to 18 in the third, etc)… 2n^2 is the equationShow the electron cloud modelShow the electron dot (Bohr’s) model
12Carbon diagramsDo both the electron cloud model, and the electron dot (Bohr’s) model
14Lonely Atoms Atoms rarely are found alone in nature They will do ANYTHING to get to 8 electrons on the outsideStealDumpShareStealing/Dumping = Ionic bondSharing = Covalent bond
15CompoundsA compound is a substance made of atoms of different elements bonded togetherResult of sharing, stealing, or dumping electronsAtoms bonded in a specific ratioThe specific ratio is very importantIf ratio gets changed it is something completely differentExample: H2O = Water …. H3O = Hydronium ionAll compounds have very different properties from eachother and of their individual componentsExample: H2O = water and it puts out water… Hydrogen and Oxygen individually both fuel fires
16Carbon Compounds (more about this later) Carbon can form many various bonds to formCarbohydratesProteinsNucleic acidsLipidsTalk about organic chemistryThese are very importantBiomolecules/macromolecules
17Ionic BondIonic bonds are formed through the electrical force between oppositely charged ionsOpposites attract!Ex: Salt aka sodium chloride (NaCl)Positive sodium (Na+)Negative chloride (Cl-)Ionic bonds steal and dumpThese bonds occur between metals and nonmetal elements
18NaCl – ionic bond Do NaCl ionic bond example Have class figure out how many particles in Na (11 protons, 11 electrons… energy level is 2,8,1)Have class figure out how many particles in Cl (17 protons, 17 electrons… energy level is 2, 8, 7)Draw electron cloud and then electron dot of both Na and ClShow how Na give 1 electron to ClIts easier to give 1 electron than taking 7, right?Now add positive charge to Na and negative charge to ClOpposites attract
19Ions Ions are atoms that have gained or lost one or more electrons. Results in a change in electrical chargeGain e becomes negativeLose e becomes positiveIons are the elements involved in ionic bondsIn previous slide sodium was a positive ion, which was denoted Na+Chlorine was a negative ion, denoted Cl-
20Ions, cont. Very important to organisms Hydrogen ions (H+) needed to produce chemical energy in cellsCalcium ions (Ca2+) needed for all muscle movement in your bodyChloride ions (Cl-) needed for many chemical signals in the brainWe cannot function w/o these ions
21Covalent Bond Not all atoms easily gain or lose their electrons! Some atoms share their electrons instead!Covalent Bond: forms when atoms share a pair of electronsUsually a very strong bondAtoms may have several covalent bonds to share several electronsRemember ionic bonds dump or steal electrons to form ions, and then the oppositely charged ions attract… opposites attractCovalent bonds share electrons instead of dumping and stealingThese bonds are between 2 non-metalsAre pretty strong bonds
22H2O – covalent bond Show H2O example Have class come up with particles in Hydrogen (1 proton, 1 electron… energy level 1)Have class come up with particles in Oxygen (8 protons, 8 electrons… energy level 2, 6)Draw electron cloud & electron dot of eachShow how they combine
23CO2 – covalent bond Show CO2 example Have class come up with particles in Carbon (6 proton, 6 electron… energy level 2, 4)Have class come up with particles in Oxygen (8 protons, 8 electrons… energy level 2, 6)Draw electron cloud & electron dot of eachShow how they combine
24Covalent Bond, cont.Molecule: two or more atoms held together by covalent bondsEx: carbon dioxide (CO2)Carbon atoms needs 4 electrons to fill outer level, oxygen needs twoCarbon shares with 2 oxygen!
29Objectives Bonds break and form during chemical reactions. Chemical reactions release or absorb energy.So we have done a little with reactions already. Showing the different bonds that may resultWho remembers the different bonds we have covered and what they are?Covalent… Sharing of electrons between 2 nonmetalsIonic… dumping/stealing of electrons between a metal and a non metalHydrogen bond… a weak bond between hydrogen and a electronegative element such as oxygen
30Evidence of a chemical reaction Temperature changeFormation of a solid (precipitate)Color change (sometimes)Odor (sometimes)Formation of gasGive examples of a chemical reaction…LightTemperature changeColor change (sometimes)Odor change (sometimes)Etc.
31Chemical Reactions Chemical Reaction... Gummy bear torture Poor gummy bear…Example of a chemical reactionMagnesium oxide demoHCl demo
32Chemical Reactions Bonds break & form during chemical reactions Plant/Animal cells break down sugars to get usable energyCells build protein molecules by bonding amino acids togetherChemical reactions change substances into different substances by breaking and forming chemical bondsSo bonds break and form during chemical reactionsChemical reactions have 2 or more reactants that form something different, which is at least 1 productShow example of a reaction
33Chemical ReactionsReactants are the substance changed during a chemical reactionsOxygen (O2) & Glucose (C6H12O6)Products are the substances made by a chemical reactionCarbon Dioxide (CO2) & Water (H2O)6O2 + C6H12O CO2 + 6H2OHere is a example of a chemical equationThis is cellular respiration which we will be getting into in a upcoming chapterThe reactants are oxygen and glucoseThe products are carbon dioxide and waterThe inverse of this equation (6CO2 + 6H2O -> 6O2 + C6H12O6) is photosynthesisReactantsProducts
35It’s all about the energy Energy is needed to break bonds in moleculesBond energy is the amount of energy that will break a bond between two atoms.Every atom has different bond energyA SPECIFIC amount of energy is needed to break bonds in an oxygen moleculeA SPECIFIC amount of energy is needed to break bonds in a glucose moleculeEnergy is released when bonds are formedThe amount of energy released is equal to the energy that breaks the same bondEnergy needed to break apart water molecule = energy released when hydrogen & oxygen atoms bond to form a water moleculeTo break bonds we need energyEvery atom has it’s own unique bond energyBond energy is the amount of energy that will break a bond between 2 atomsWhen bonds are formed, energy is released, which is equal to the amount of energy it took to break the bonds
36Chemical Reactions All chemical reactions involve changes in energy Energy added to the reactants breaks their chemical bondsWhen new bonds form in the products, energy is releasedEnergy is both absorbed and released during a chemical reaction!Some release more energy than they absorb (Generous)Some absorb more energy than they release (Greedy)To break bonds energy must be addedWhen bonds form energy is releasedIn a chemical reaction, energy is both released and absorbedHowever some will release more energy then they absorb. They are generous reactions.Some absorb more energy than they release. They are greedy reactions.
37Chemical Reactions, cont. Generous chemical RXNs that release more energy than they absorb= Exothermic reactionExcess energy is the difference in bond energy between the reactants and productsExcess energy is often released as heat or lightCellular respiration releases usable energy for your cells & heat!The generous reactions that release more energy than they absorb are call exothermic reactionsOr in biology they are called exergonicRemember binomial nomenclature… Exo means outside… Exoskeleton is skeleton on the outsideThis excess energy that is released is the difference in bond energy between reactants and productsThis excess energy is often released as heat or light.A example of exergonic reaction is cellular respiration
38Chemical Reactions, cont. Greedy chemical RXNs that absorb more energy than they release= Endothermic reactionIn photosynthesis, plants absorb energy from sunlight and use that to make sugars and carbohydrates
39Exothermic VS. Endothermic graphs Draw a exothermic graph, labeling reactants, products, activation energy, and energy released.Draw a endothermic graph with the same
40But how does a rxn start?Some energy must first be absorbed by the reactants in ANY chemical reactionThe amount of energy needed will varyActivation energy is the amount of energy that needs to be absorbed for a chemical reaction to startPush a rock up a hillActivation energy is the energy that needs to be overcome for the reaction to startLook at the pictureExplain the boulder example
42Catalysts & EnzymesA catalyst is a substance that lowers the activation energy needed to start a chemical reaction.Special proteins called enzymes are the biological catalysts that speed up the rate of chemical reactions in biological processes.Activation energy is the energy that needs to be overcome for the reaction to startLook at the pictureExplain the boulder example
46Objectives Life depends on hydrogen bonds in water. Many compounds dissolve in water.Some compounds form acids or bases.
47THE IMPORTANCE OF WATER CELLSOrganisms’ bodies, (their _____________),are made up of mostly ____________________The water in cells gives the cell _______________and ___________________ materials withinorganisms.All of the processes necessary for anorganism’s life take place within the______________________________ of the cellWATERSTRUCTURETRANSPORTSOur cells are made mostly of waterWater gives cells structure & helps transport materials withinAll processes necessary for an organism take place within the watery environment of the cellThis watery environment is called the aqueous environment of a cellWhat does aqueous sound like?AquaWhat does aqua mean?Aqua means waterBreaking words apart is so important in biologyWATERY ENVIRONMENT
48PROPERTIES RELATED TO HYDROGEN BONDS ______________________ HIGH SPECIFIC HEAT2. COHESION3. ADHESION______________________2. ______________________3. ______________________Specific heat is the amount of energy it takes to raise the temperature 1 degree CelsiusCohesion is attraction among the same moleculesAdhesion is attraction among different molecules
50HYDROGEN BONDS O H H POLAR UNEQUAL ELECTRONS HYDROGEN POSITIVE Negative ChargePOLAROWater is a “______________” moleculeForm when atoms in a molecule have ____________ pulls on the _____________ they share.Opposite charges of polar molecules can interact to form ____________________ bonds.An attraction between a slightly _______________ hydrogen atom and a slightly ______________ atom.(Usually _______________________________)Hydrogen bonds are part of the structures of _______________ and of ______________UNEQUALELECTRONSHHPositive ChargePositive ChargeHYDROGENShared ElectronsPOSITIVENEGATIVEOXYGEN OR NITROGENPROTEINSDNA
51COHESIONCohesion: the attraction among __________________ of the same substance.Cohesion from hydrogen bonds makes water molecules _____________________.Cohesion produces __________________, ( “skin on water” )MOLECULESSTICK TOGETHERSURFACE TENSIONAttraction among the same moleculeWater has cohesion to other water molecules
52ADHESIONAdhesion: the attraction among __________________ of ______________ substances.For example, water molecules stick to other things.Water in a test tube, (water is attractedto the ____________)MOLECULES DIFFERENT?GLASSAdhesion is attraction among molecules of different substancesShow penny demo (water droplets on a penny)
53MOLECULES DISSOLVE IN WATER Materials such as ________________ and ____________ cannot be transported form one part of an organism to another unless they are dissolved in blood, plant sap, or other water based fluids.______________: Mixture of a substance that is the same throughout.___________: Substance that is present in the greater amount and dissolves another substance.___________: Substance that dissolves in a solvent.MOLECULES DISSOLVE IN WATERSUGARSOXYGENSOLUTIONSOLVENTWater is a polar moleculeIt means that part of it is partially negative, and another part is partially positiveSolution is a mixture of a substance that is the same throughoutA solvent is a substance that is present in the greater amount and dissolve the other substanceSolute is the substance that is being dissolvedThink of the north and south poles, they are oppositeWater being polar can dissolve other polar substances such as sugars & ionic compounds b/c weaker attraction between polar & nonpolar than 2 polarWater doesn’t dissolve oil/fats/lipsExample of a cup of water and table saltExample of a cup of water and vegetable oilSOLUTE
54Mixtures Heterogeneous Homogeneous A mixture with easily separated parts with their distinct propertiesA mixture that it the SAME throughout and hard to tell individual characteristics
55ACIDS AND BASES BASE: Compounds that Some compounds form ______________ or _____________because they _______________ into _______________when they dissolve in ___________.BASE: Compounds thatremove H+ ionsfroma solutionACIDS BASESBREAK UP IONSWATERACID:Compoundsthat releasea proton a hydrogen ion(H+) – when it dissolvesin waterAcids & bases break up into ions when they dissolve in waterAcids release a proton (H+) when it dissolves in waterBases remove protons (H+) from solution
56soap More acidic More basic neutral The pH scale is a scale from 0 to 147 NeutralTo the left of 7 is acidic, 0 being the strong acidTo the right of 7 are bases, 14 being the most basicThe pH scale is logarithmic, which means each # you move up or down on the scale, there is a difference of 10 fold in relative basicity/acidityMore acidicMore basicneutral
58Review How does the structure of water make it a good solvent? What are the similarities and differences between solutions and suspensions?What are the differences between acids and bases?
59The Building Blocks of Life Section 4The Building Blocks of Life
60Objectives Carbon atoms have unique bonding properties. Four main types of carbon-based molecules are found in living things.
61BUILDING BLOCKS OF CELLS PROTEINP____________________LIPIDSRL____________________CARBOHYDRATESOIC____________________ATPTPAA____________________So these are the building blocks of cellsThese are the important macromoleculesNNUCLEIC ACIDEIRT____________________AIDBPN
62CarbohydratesCarbohydrates are molecules composed of carbon, hydrogen, and oxygenInclude sugars & starchesCan be broken down to provide useable energy for cellsMajor part of plant cell structureThe most basic carbs are simple sugars, monosaccharidesPolysaccharides are polymers of monosaccharidesCarbohydrates provide energy used by your cellsExamples are sugars (sucrose is table sugar or candy; fructose is fruit sugar; glucose) & starches (grains, potatoes, rice, bread)Carbohydrates such as complex starches are major part of plant structureMonosaccharides are simple sugars and the most basic carbsPolymers of monosaccharides are called polysaccharides.. Mono means 1, poly means multi.
63CARBOHYDRATESUSED BY CELLS FOR __________ ___________ AND __________ ____________.SIMPLE CARBS = _______________________________COMPLEX CARBS = __________________________________________________________ENERGY SOURCEENERGY STORAGEONE OR TWO SUGAR MOLECULESLONG CHAINS OF SUGAR MOLECULESEx) Starches such as potato,pasta, bread________________________________Note only are carbs used as an energy source, but also for energy storageSimple carbs are just one or two sugar molecules whereas complex carbs are very long sugar chains
64ProteinsProteins are the most varied of the carbon-based molecules in organismsHave a role in movement, eyesight, digestion, etc.A protein is a polymer made of monomers called amino acidsAmino acids are molecules that contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfurOrganisms use 20 different amino acids to build proteinsThe body makes 12 of the 20, the other 8 come from foodProteins vary greatlyTheir roles are vary greatlyAmino acids are the monomer that is the building block for proteinsTherefore proteins are the polymer of amino acidsAmino acids contain many of those important elements that we talked about a week or two ago. Remember CHOPSN?There are a total of 20 amino acids that we use as building blocks for proteinsHowever our body can only readily make 12 of the 20. We get the other 8 from foods we ingest.The 12 that we make are called the 12 nonessential amino acids, because we make themThe 8 that we do not make are considered essential, because it is essential you supplement your body with them
65These are the 20 amino acids The ones with the arrows next to them are 8 essential (body doesn’t make them) amino acidsThe ones without the arrows are the 12 nonessential (body does make them) amino acids
66PROTEIN CELLS MAKE UP _________________. INVOLVED IN ALL _______ ____________.BUILDING BLOCKS = _________ __________._________________= TYPE OF PROTEIN THAT STARTS AND SPEEDS UP CHEMICAL REACTIONS IN CELLS.LIFE PROCESSESAMINO ACIDSENZYMEAmino acids make up proteins, and proteins make up our cellsVery important, and are involved in all life processesThat means they have many functions and tasksEnzymes are proteins that speed up and help start chemical reactions in cellsEnzymes are catalysts
67LipidsLipids are nonpolar molecules that include fats, oils, and cholesterolContain chains of carbon bonded to oxygen & hydrogenSome broken down for useable energyOthers are part of a cell’s structureFatty acids are chains of carbon atoms bonded to hydrogen atoms.Saturated fatty acids have single carbon-carbon bondsUnsaturated fatty acids have double carbon- carbon bondsLipids are made of CHO (carbon, hydrogen, oxygen; some of those IMPORTANT elements again)Lipids are nonpolarSince they are nonpolar that means they cannot be dissolved in waterInclude fats, cholesterol, and oilIf you have a glass of water and put some vegetable oil in there what happens? It floats because water cannot dissolve itCells use them for structure and for energyFatty acids make up lipids2 types of fatty acidsSaturated and unsaturatedSaturated have a carbon-carbon SINGLE bondUnsaturated have a carbon-carbon DOUBLE bond
68The top is a example of a saturated fatty acid b/c it has single carbon-carbon bonds. The bottom is a example of a unsaturated fatty acid b/c it has double carbon-carbon bonds.See the black lines?Also notice the difference in structure.
69LIPIDS WATER DON’T MIX WITH ______________. PHOSPHOLIPIDS – MAKE UP ________ ______________.FATS AND OILS THAT _________ ___________.ORGANISMS USE FATS AND OILS WHEN THEY HAVE USED UP ___________________._________- SOLID AT ROOM TEMPERATURE._________- LIQUID AT ROOM TEMPERATURE.CELL MEMBRANESTORE ENERGYCARBOHYDRATESFATSAgain, lipids do not mix with water. This is because they are nonpolar. In addition many are LESS dense than waterLess dense than water means less than 1.0g/ml, but also tells you it will float on waterFats & oils store energyAfter a organism uses energy from carbohydrates, they will tap into the stored energy from fats and oilsWhat is the difference between fats and oils?Their state of matter at room temperature!Fats are room temp whereas oils are liquid at room tempOILS
70ATP MAJOR ___________ ___________ MOLECULE IN CELL. ENERGY CARRYING ENERGY IN __________________ AND __________ AND _____________________ MUST BE TRANSFERRED TO ATP IN CELL TO BE USED.ENERGY CARRYINGCARBOHYDRATES LIPIDSPROTEINSSo we talked about how cells use these macromolecules for energyMacromolecules like carbs, lipids, and proteinsIn order for their energy to be used, a cell must transfer their energy to ATPATP stands for adenosine triphosphateATP is a major energy carrying molecule for cells
71Nucleic AcidsDetailed instructions to build proteins are stored in extremely long carbon-based molecules called nucleic acidsNucleic acids are polymers that are made up of monomers called nucleotidesNucleic acids differ from the other carbon- based moleculesThe others have a large # of functionsNucleic acids have just 1 function… make proteinsDNA stores info for putting amino acids together to make proteinsRNA helps to build proteinsThe instructions to build proteins come from nucleic acidsNucleic acids are very long carbon-based moleculesThey are made of nucleotidesNucleic acids are the polymer; Nucleotides are the monomerNucleic acids only serve 1 purpose; whereas other carbon-based molecules have manyTheir sole calling in existence is to make proteinsThere are two nucleic acids in particular that helpDNA = Deoxyribose nucleic acidRNA = Ribosomal nucleic acidDNA store the info for putting the amino acids togetherRNA helps to build the proteins
72NUCLEIC ACIDS HAVE ALL INFO NEEDED TO MAKE __________. PROTEIN “_______________” OF LIFE.BUILDING BLOCKS OF _____________.TWO TYPES: ________ AND _______.PROTEINBLUE PRINTNUCLEOTIDESDNA RNA
73Monomer & polymerEach subunit of a complete carbon- based molecule is called a monomerA polymer is a large molecule, or macromolecule, made of many monomers bonded togetherMonomers of a polymer may be the same (ex. Starches)Or different (proteins)So we have covered this already but it is important to knowEach unit of a carbon-based molecule is called a monomerA polymer is made of many monomers togetherStarch polymers are made from many of the same monomers togetherProteins are many difference kinds of monomers bonded together
74COMPOUND BUILDING BLOCK (POLYMER) (MONOMER) PROTEIN AMINO ACIDLIPID (FAT) FATTY ACIDCARBOHYDRATE SUGARSNUCLEIC ACIDS NUCLEOTIDESo as a review here are the carbon based polymers we have gone overAnd also here are the monomers or building blocks that make them up
75Review What is the role of carbon in living organisms? What are the four major families of biological macromolecules?What are the functions of each group of biological macromolecules?