Biology – the study of living thingsDNA – genomicsElephant – zoologyInsects – entomologyMicroorganism – microbiologySnake – herpertologyCells (tissue) – histologyScientific method – scientists use this – observe, ask questions, formulate and test hypothesesNull hypothesis – no significant difference among data - what’s not going to happenPositive control – always gives consistent dataNegative control – doesn’t give you a positive resultIndependent variable – manipulating variableDependent variable – measuring variableLife:Energy utilizationMade up of cellsInfo processingReplicationEvolutionThe cell theory – all cells come from cells – cells are basic structural and physiological units of all living organisms – building blocks of lifeSpontaneous generation hypothesis – cells come from no whereAll cells from cell hypothesis – cells come from preexisting cellsTheory of Evolution by Natural SelectionBuffon – earth is older than ever belivedCuvier – extinction occurred (documented fossils)Lamark – living species might change over timeLyell – geological forves gradually shaped earth & still do soDarwin – orgin of speciesWallace – theory of evolution by natural selectionSpecies are related by common ancestryNatural selection – individuals in a population vary in characteristics that are heritableAdaptions – characteristics that increase fitnessCertain versions of heritable traits help individuals survive better and reproduce more than others (fitness)Natural selection acts on individualsEvolutionary change occurs in populationsArtificial selection – done by humans – certain trait that we are selecting forWoese – tree of lifeBiological NomenclatureTaxonomy – classification of organismsBinomial –SpeciesHierarchal categorization based on evolutionary relationship: domain, kingdom, phylum, class, order, family, genusHow life began:Spontaneous generation must have occurred oncePattern: observation: atoms  molecules  complex moleculesProcess: testing it: energy96% or organic matter consists of O, N, C, Han atom is electrically neutral when the # electrons = the # of protonsnon-neutral atoms are called ionselectrons move around nucleus in specific orbitals (s,p,d,f)1st orbital – 2 electrons2nd orbital – 8 electronselements are defined by the # of protonswhen you change protons, you get a different elementwhen you change nuetrons, you get an isotopeIsotope – same # protons, different # nuetronsUsed in PET scans (medical imaging)Atoms of Life:Cl – traffic in membrane in cellS – disulfide bridgesMg – bonesP – DNANa – important for human body muscle contraction & propagation of nucleusAn atom is most stable when its valence shell is filledChemical Bonding:Covalent bond – results from electron sharing (orbital overlap)Polar covalent – unenven/unequal sharing of electronsPolar covalent – equal sharing of electronsIonic Bonding – results from transfer of electrons between 2 atomsPolarityElectronegativity --- O > N > C = HLaw of Conservation of Mass: mass is neither created nor destroyed in a chemical reactionGeometry of Simple molecules:Tetrahedral shape, bent shape, linear, ect.Basics of Chemical Reactions:Mole = 6.022 x 10^23Water = 18.02 g/molMolarity = mol/LWaterHydrogen bond – electrostatic attraction between moleculesH bonded with F, N, OHydrophilic -- “like dissolves like” -- polar dissolves polarHydrophobic – polar will NOT dissolve nonopolarProperties:Structure – small, bent shape, polar covalent bonds, polar moleculeFunction – cohesion, adhesion, surface tension, density of water, high specific heatCohesion – attraction between like moleculesAdheasion – attraction between two different moleculesSurface tension – strength of molecules on surfaceWater is more dense as a liquid – because the molecules are closer togetherWater acts as a weak acid and a weak baseEquilibrium reactionAcid – proton donorBase – proton acceptorpH = -log [H+]measures concentration of protons [H+] in a solutiona substance with a pH of 9 is 10x as basic as a substance with a pH of 8 – pH is 10x as you move up the scaleperiodic trendsatomic size = increases down and to the leftelectronegativity = increases up and to the rightionization energy = increases up and to the right*specific heat – the amount of energy required to raise 1gram of it by 1oCthe temperature on the planet does not change a lot b/w day & nightchemical equilibrium – rate from L to R is = R to Lbalanced chemical reaction – L and R are evenendothermic – gains heat – ex. Boiling waterexothermic – gives of heat – ex. CondensationEnergy – ability to do work or to changeTransformation of energy is a hallmark of lifeTwo types:potential energy – stored energykinetic energy – energy if motionFirst Law of Thermodynamics: energy is neither created nor destroyed in a chemical reaction; energy before = energy afterSecond Law of thermodynamics: when energy is converted from one form to another, some of that energy becomes unavailable to do workEntropy – unavailable Energy in an enclosed system – amount of disorderGibbs Free EnergyG = H - TSG < 0 ---- free energy released; exergonic; spontaneousG > 0 ---- free energy consumed; endergoinic; nonspontaneousG = 0 ---- chemical reaction is at equilibriumImplications of second law of thermodynamics:Disorder tends to increase because of energy transformationsLiving organisms must have a constant supply of energy to maintain orderSpontaneous process results in lower potential energy, increase disorder (higher entropy), or bothIncreased temperature speeds up a reactionIncreased concentration of reactants speed up a chemical reactionFunctional Groups:Amino - NH2 - amines - acts as a base (attracts protons)Carbonyl - CH2 - aldehydes / ketones (react with certain compounds to produce larger molecule with form)Carboxyl – CHO2 – carboxylic acids (acts as an acid)Hydroxyl - OH - alcohols (acts as a weak acid and drop a proton)Phosphate – PO4 – organic phosphates (carry 2 charges; change in charge affects recipient molecules)Sulfhydryl – SH – thiols (can form disulfide (S-S) bonds that contribute to protein structure)In the case of chemical evolution, the pattern that is increasingly complex carbon-containing molecules formed in the atmosphere and ocean of ancient Earth. The process responsible for this pattern was the conversion of energy, from sunlight