BIOL 1100 Midterm #1 Review (Chapters 1-4) PDF

Summary

This document is a review for a biology midterm, covering chapters 1-4. It discusses scientific method, cell structure and function, energy, and enzymes. It's a useful resource for students preparing for a class on introductory biology.

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Chapter I PurplePages Scientificmethodin making observations developing explanations testingthoseexplanations hypothesis tentativeanswer must be testableand falsifiable onlysupported neverproven Experimentation controlledexperiment comparesexpgroupwith control group Independent...

Chapter I PurplePages Scientificmethodin making observations developing explanations testingthoseexplanations hypothesis tentativeanswer must be testableand falsifiable onlysupported neverproven Experimentation controlledexperiment comparesexpgroupwith control group Independent changed scientist variables by Dependentinresponsetochangesin independentvariable controlled remainsconstant scientific theory w scientificallyacceptable andwellsubstainedexplanation ofsomeaspectof thenaturalworld LOTSOFDATA Biology astudy of livingthings cellbasicunit of life Organizationofmatter umatterhasmass andoccupies space Elementscannot be broken down chemical vans two or more by compound n elements in fixedratio CHON makeup 96 of livingthings u variationcomesfrom different proportions of those elements and organization AtomicStructure Afflictma ofp n n Electron mass is negligible Isotopes have same p different n different atomicmass n Radioisotopenunstable isotopes that and release energy decay Radioactivetracers in use radioisotopes to measure speedof chemicalprocesses and or movementof substance nEx radioactiveiodineto measure thyroidgland radioactivity Electrons Same as p move in orbitals are pained orbitals are grouped Valence electrons Hittite'snest heartdetainittmanitmichteBras ftp.t nboch ioniccovalent hydrogenbonds van derWaals Ionic n transferof electronsresulting in chargedatoms ions w intramolecular covalent n sharepairof electronsindistinct 3Dform a intramolecular Electronegativity measure of an for electrons atomsattraction Polarmolecules wunequalsharing resulting in partialcharges Hydrogenbonding partial charge of H atomattracted to partial charge intermolecular weakerthan covalentandionicbut collectively canbecomestronger VanderWaals u weakest developebetween nonpolarmolecules constantmotion of electrons causesthemto segregate on one side of molecule partial charges creating Hydrogen Bondsand Water Liquiddynamic moredense solidstable lessdense waterhasahigh specific heatcapacity liquid at roomtemp cohesion w attractionbetween watermolecules allowswaterto moveagainst gravity waterin universalsolvent 11dissolved substancein solute watermolecules surround polarmolecules and ions creating separation WaterIonization and pH ityfftoahsfkf.inlisbaaeTeimihetbya'there of Ht us OH n measured on pHscale ftp.tfaEHaspuyeaY absierg releasing Ht ncarbonicacid bufferin our blood CarbonCompounds livingmatterisorganic containscarbon has4bondswhichallowfor largecomplex molecules hydrocarbons onlyhydrogen andcarbon carbonbondswith covalentbonds Functional Groups areactive groupsthatenterin biological rans and bindto carbon it Dehydration and Hydrolysis Rans synthesis of a polymer throughdehydrationreaction createsbond breakdown of a polymerthrough hydrolysis rxn breakingdownusingwater addingwater breaksthebond ante qngugbayiaingmateri.ae Isomer same chemical formula butdifferentmolecularstructure and Enthrmers mirroron isomers Gtu andFru are structuralisomers Disaccharide two sugars sugar Proteins manystructures and functions workforce of cell structuralsupport storage transport enzymes communication movement a proteinis one or more polypeptides polymersmade of aminoacids mar 1ThKgetherwithpeptidebondscovalent linkedbydehydration mono synthesis aminoacid at carboxyl end ProteinStructure Primary a linearsequence of aminoacids not functional no structure Mood Secondary w H bondsbetweenamino acidsandcarboxyl groups 0and H of backbone toldcreating helixandβpleatedsheets notfunctional Tertiary bondsbetween w R groupscreating 3Dshapeand function Quarternary 22polypeptides allbondtypes functional n Prostheticgroups w non proteincomponant added to proteinsto makethemfunction heme NucleicAcids Imagisticinformation inheritance YmEEetktffa.serPff 584 Nucleotides 3 partsjoinedbycovalent bonds nitrogenousbasepentosesugar1 3Pgroups nuracil only in RNA thymine onlyin DNA nadanineandguanine usedin gaffer Structure 2nucleotidechains sugar phosphatebackbone phosphodiesterbonds insidewith H bonds fakeL39 Lipids definedmonomer hydrocarbon backbone 1444449 s saturatedfats max H atoms no doublebonds unsaturatedfats gave I or moredoublebond bendsKinks up ftp.yg for Cells composed ofmacromolecules structuralorganization of the macromolecules determines the function of cells Chapter 2 Thecell an overview Thecellis thebasic unit of life byHooke in discovered 1 Tryin ms are composed of 1 or more cells 3 t meM Ytpe f ig 9hdfunctional unit of life Prokaryotic vs Eukaryotic Cells Prokaryoticcells unonucleus or mbbound organelles w onecircularDNAin unboundregion nucleoid uplasmamb for respiration and photosynthesis uflagella andpili cilia usevariety of substancesfor energy and carbonsources to synthesize organic molecules w outnumber w livein all allotherorganisms regionsof earthssurface versetaile extremely Eukaryoticcells are largerbecausetheycan overcomethe surface to volume ratio since theycontain membranebound organelles Parts of a EukaryoticCell Nucleus n contains genes enclosed by nuclearenvelopecontainingnuclearpore complex uDNAandproteins chromatin inchromatincondenses chromosomes nucleolusis in nucleusand issiteof ribosomal RNAsynthesis Ribosomes madeof ribosomalRNA andprotein largeandsmallsubunit carryoutprotein synthesis of ER or nuclearenvelope tenifYet Lmfiends meYuhi tace TheEndomembrane System collection of interrelatedmembranous sacs organelles Idaheated nuditten plastic re www.tgoigi apparatuslysosomes vesiclesplasmam rethano p Thigh ribosomesattachedmakesproteinsfor cellmbor secretionattached to nuclearenvelope insmooth no ribosomes synthesizeslipidsand breaksdowntoxicsubstances fi fftemifHfcsdpit7Petites secreted orembeded inplasmamb or lysosomes Lysosomes membranoussacs of hydrolyticenzymes digestmacromolecules autophagy recyclecells organelles or macromolecules winvolvedin phagocytosis Vesicles Mitochondria Inmake u as 849 9 18,11 proteinsfrom free ribosomes doublemb Imf Tondrialmatrix Cytoskeleton Ymeratate function faithahaaum.it naimreitybues nsupportandshape winteractwith motorproteins motility monorails forvesicletraffic regulatebiochemical activities Centrosome and centrioles umicrotublesgrow from centrosome centrosome microtubleorganizingcentre incentrosome has pair of centrioles Peroxisomes uspecializedmetaboliccompartmentsbounded asinglemb by function converttoxic hydrogenperoxidetowaterusingcatalase Chloroplasts IP photosynthesis Imhaakfiftein fromfreeribosomes indoublemb grana Vacuoles 88 formedby phagocytosis contractilepumpexcesswater outof cell Central inplants holdorganiccompounds and water Ghorkssupportprotection and are perforated with plasmodesmatas Animal Cell Surface cellsurfacemolecules aid in cellcontact communication and organization Celladhesionmolecules glycoproteins in plasma mb maintain bodyform andfunction attachand detach duringdevelopment cell recognition adhesion site for pathogens Yfight ve pressed together noleakageof extracellularfluid fastencellstogetherintosheets desmosomes anchoring gap communicating providecytoplasmicchannelsbetweenadjacent cells Chapter 3 Energyand Enzymes Literequirestempsbelow 100 C w o enzymes lifewouldnot exist Energyis the capacity to do work Et.EEiEi EEfae irmae mechanical cnn.ae Thermodynamics studyof energy and its transformations 48 L exchange energybut not matter Yokated 84Thahger feherggaotrm.ithumans 1ˢᵗLaw of Thermodynamics energy can be transformed but not created or destroyed total energy in system and surroundings is constant 2ndLawof Thermodynamics witheverysecond thetotal disorder of a system and its surroundings increases Entropy measure of disorder randomness Example of 2ndLaw only 30 of Chem energy in gas becomes mechanical energy the rest becomes thermalenergy randommotion ofmolecules disorder Spontaneous rxn chem or phys ran that occur without an input of energyfrom tTonfYb h's98spontaneous ans of system 2 8847814 ΔEnthalpy spontaneous ran it products have lesspotentialenergy than reactants in system iEh fd m Exothermic ran h f releasestherapy energy ΔEntropy Freeenergy DG portionof system'senergy available to dowork DG OH TO Δ Entropy enthair absolute temp fffffneff f.IE hfaffpl.at a hphihctseiheta'staff dammit Eighty YeahYouPrint8 Eiche 1 1 19alive ITEMYared Joe tagainst 2nd Law bringin energy and matter to generate nfrgah.isYmtsQteledaiIhart and byproducts whichincrease disorder of surroundings 1k ftp 8a f aa ieonefeE9gy'Triantiation its metabolicpathway sequential rxus products become reactants catabolic pathwayw energy is released breakdown of complex molecules tosimple ones Anabolicpathway energyis consumed build complicated moleculesfromsimple ones ATPorATPhydrolysisreleases freeenergy used in cells hydrolysis of ATP exergonic ran coupled to make endogonic ran spontaneous uncoupling rans requires energy ATPused forthis is replenished urns replenishingATPlink ATPsynthesis to catabolic rans ATPcycle continued breakdown and re synthesis of ATP RoleofEnzymes in Biological Rxus a activation energy represents a kineticbarrier b enzymes accelerate rxns by reducing activation energydonotsupply theenergy DGsame c enzymes combine w reactants released unchanged d enzymesreduceactivation energybyinducing transition state Enzymes a ranthat is spontaneous is unrelated tothe speed of the un u enzymes specialgroup of proteins that alterspeed of rxus Activationenergy initial energy investmentrequired tostart a van even if spontaneous gainthe energyenterthetransitionstate highlyunstable moleculesthat Heatis NOTusedtospeed up vans since we can't control it disorder and it destroys macromolecules catalystinchemicalagent that speedsthe rate of ran withouttaking part Enzymesare biological catalysts Moveaboutenzymes inactivesite brieflycombines w reactantsubstrate specificinteraction enzymeis released unchanged v induced fit enzymechanges shapewhenbonded w substratethenrevertsback Enzymecofactors inorganic ions or organic nonprotein groups necessary for catalysisto occur EternitiesMortgah fasctothtimids Enzyme Catalysis ftp.tenahsfaieactivesite Forum InCHILEdate conditions that affect enzymeactivity 1 Influence of s enzyme and substrate 2 Enzymeinhibitors 3 Allosteric control 4 Temperature and pH Enzymeand Substrate wit excess substrate the rate of catalysis is proportional to amount of enzyme lowsubstrate ranrateslows enzymesand substrates collideinfrequently highsubstrate enzymessaturated withreactants reaction rate levels off Elliff tianya.fi itetiaaEiengem and decrease its activity 2 NoncompetitiveInhibitorbinds elsewhere on enzyme Fuff GIL two metabolic pathways run simultaneously in oppositedirections nooveralleffect ftp.ff.IEsffiIonf Effect generositiesbinding dignitarymolecule to high affinitystate activeform enzyme and substratebind strongly inlow state inactiveform affinity enzyme and substrate bind weakly or not at all Feedbackinhibition aproductof enzyme catalyzed pathwayacts as a regulator of the van helpsconservecellular resources TemperatureandpH eachenzymehas an optimal for each if not atoptimal ranratesfall off amostenzymespHoptimumis nearcellularcontents about 7.0 but enzymesfrom cellsmay havepHfurthurfrom neutrality Changes inpHaffectchargedgroups in aminoacidsof enzymes intemp 2effects astemp rises rate of rxn increases and hightempscancause enzymesto denature which reducestherate of ran Chapter4 Membranes and signalling Edits I Glialipidbilayer in which proteins are embedded andfloatfreely Fukh.hn phfectintrain dalttwYngaTeledithmeikhange of molecules betweencelland environment ftp.ttfffffnmofffha b proteins of one half of thebilayer arestructurallyandfunctional TheLipidFabric u phospholipids arethedominant lipid in mbs n fluidity of thelipid bilayer depends onhowdenselypacked the individual lipidmolecules are II Yo'mb i s mt ai Yne'keiIs aegfamilies giting ftp.fnatafeata Tess fluid Temp iftempdropslow phospholipids packtogetherandMbformsviscoussemisolid gel w fluiditydepends on which mb lipidsare unsaturated andmostmbsystemshave a mixedpopulation ofsaturatedand unsaturatedfatty acids AdjustingFattyAcidcomposition intheproper adjustmentof fattyacid composition by fluidityis maintained Desaturase enzymesthat produce unsaturated fattyacidsduringfattyacidsynthesis regulation of desaturase regulation ofmbfluidity increasedtemp decreasedesaturases usth tainsbalance at hightemps decreases fluidity atlow temps increases fluidity Mb Proteins 4keyfunctions Ieh ealdin phospholipid bilayer transmit Fats L depleting.mns EYegsraYYs kin4iEfigtesa9Ynewayacrossmn IfheldYuffieofmb with don'tinteract cone hydrophobic noncovalentbonds canhop on and off on by a most are on cytoplasmicside umade ofmixture and nonpolar amino up of polar acids MbTransport Passive hydrophobicnature of mbrestricts freemovementof manymolecules passivetransportmovementacross mb withoutneed for energy ATP indriven diffusion net movement of substancefromfromhigh tolow by rate of diffusiondependson the C gradient SimpleDiffusion passivetransport of substances acrosslipidportion ofmembranes with C gradients smallunchargedmoleculesmoverapidly largeor charged are impeded fromcrossing Factors that influencediffusion sizeandcharge of molecules FacilitatedDiffusion passivetransport ofsubstance at rateshigherthan predictedfromtheir lipidsolubility udependson membraneproteinsandfollows gradients u is specificfor certain substances and can become saturated at of transported substance high TransportProteins for FD I spec singlestinksissats ana aminoacross mesawssa differences ftp.tffEiEf as Ews T.int mieh eine he to hypertonicsolution high c solute Active requires a direct or indirectinput of energy derivedfromATPhydrolysis insubstances movedagainst gradient depends on mbtransportproteins uspecificfor certainsubstances can besaturated whenalltransportproteins are busy First primaryactivetransport proteinthattransports substancealsohydrolyzesATPtopowertransport Secondsecondaryactivetransporttransportindirectlydriven ATPhydrolysissincethetransport proteindoes notbreakdownATP rather a favourable by gradientof ionsis theenergysource PrimaryActiveTransport moves chargedionsacrossmb HtpumpscastpumpNatktpump Summary Tocreate an electrochemical gradient difference andan electricalchargedifference highpotentialenergy Mbpotential voltagedifferenceacross a mb move on outside less on inside EnergyfromECgradient isused in SecondaryAT Symportco movesthroughmbchannel in t ransportedsolute me asdrivingion ionscomebackacrossfollowingtheirCG direction antiportdrivingionmovesthroughmbchannel inonedirection vidingenergyforactivetransportof anothermolecule in oppositedirection Transportinglargersubstances w Exocytosis andEndocytosis umovelargermolecules and particles in andout of cells bothrequireenergy Exocytosis materialsfromrough ER reachgolgi packagedin secretoryvesicle carriessecretedMateria andfuseswithplasmambreleasingcontents to cellexterior Eff Lephhhhygynytoplasm cellareenclosed plasmamb Endocytosisw materialsoutside by wmbpocketsinwardandforms endocyticvesicleon cytoplasmic side a 2forms bulkphase pinocytosis Receptormediated endocytosis EXO pino RME celleatinganothercell pseudopodsclosearound Phagocytosis preypreygoesin endocyticvesicle incytoplas Cell Communication unimportant in multicellular organisms b c it determines it a cell is normal of it a cell is undergoing apoptosis cell death assignat ad s aka'sconverted into aspecificcellular response Intercellular Chemical messengers u controllingcell synthesizes specificmolecule thatacts as a signalingmoleculeto affectactivity of thetargetcell Tretton178kEur shes SurfaceReceptors signal transduction g Life em banknote signal change in the receptor that activatesits ftp.iahssmitenaaEfrlahsilfingheaus molecular p CellularResponsePathways signaltransductionpathway ubindingofsignalmoleculetosurface receptortriggerscellularresponsewithoutenteringtheall thesignalis relayed inside byproteinkinases TroteinKinaseswturns on transduction pathway ETI.tn satortYnhitsfsaPchtYPYes ff p efpmwte.tn ptowatuacngetfYuYaifiesPp Pehorylation Balancing CellularResponse Pathways Proteinphosphates a reverseresponse enzymes that remove phosphate groupsfrom the targetproteins turns off signaltransductionpathway Amplification increasein magnitude of signal foreachstep reach enzyme activates 100s 1000s ofproteinsthat enternextstep allowsfull internalresponsewhen only afew signal molecules bindto receptors

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