Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
1
BiologicallyImportantMoleculesIntroductionWehavealreadyseeninourstudyofbiochemistrythatthemoleculesthatcompriselivingthingsarecarbon-based,andthattheyarethoughttohaveoriginatedfrominorganicmolecules.Itisthoughtthatinlivingorganisms,thereareover10,000compoundsthatexisttohelptheorganismfunctionThesecompoundsbelongtofourmajorgroupsofbiologicallyimportantmoleculesthatperformfourmajorfunctionsinlivingthings:
● Energystorage● Cellularstructure● Cellularregulationandcommunication● Informationstorageandtransfer
Butwhatdothesemoleculeshaveincommon?Aretheredetectablepatternsthatexistamonggroupsofmoleculesinlivingorganisms?Howarethesemoleculesassembled?We’llexploretheanswerstothosequestionsinthisactivity.
FindingPatternsinBiologicallyImportantMoleculesThemoleculesthatmakelifepossiblearebuiltoffofcarbonbackbones,whichactasscaffoldsfortheotheratomsfoundinorganicmolecules--namelyhydrogen,oxygen,nitrogen,phosphorusandsulfur.Buttheseatomsarenotusuallyfoundassoloatomsbranchedoffofthecarbonbackbones.Theyaremostoftenfoundasgroupsofatomsknownasfunctionalgroups.Thesefunctionalgroupsareclustersofatomsfoundtogetherthatprovidemoleculeswithcertainchemicalproperties,suchaspolarityoracidity.Themostimportantfunctionalgroupsfoundinbiologicallyimportantmoleculesareshowninthechartsbelow.
FunctionalGroups:Thesearethemostcommonfunctionalgroupsfoundinthefourclassesofbiologicallyimportantmoleculeswe’llbeexploring.DIRECTIONS:First,cutapartthemoleculecardsyouhavebeengiven.Thereare42differentbiomoleculesonthesecards.Next,identifyandmarkthefunctionalgroupsyouseeonthemoleculecardsinthefollowingway:● Hydroxylgroups:circleinred● Aldehydes&Ketones:triangleinorange● Carboxylgroup:boxthegroupingreen● Aminogroup:triangleinyellow● Phosphategroup:circleinpurple● Sulfhydrylgroup:boxthegroupinblue
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
2
Noworganizethemoleculecardsintogroupsbasedonsimilaritiesintheirstructure.Whengroupingthemolecules,paycloseattentiontothefollowing:
● Thefunctionalgroupsthatarepresent● Theshapeofthemolecule● AnypatternsyouseewithinthemoleculeNowlet’slookatthefourmajorgroupsofbiologicallyimportantmolecules:● Carbohydrates● Lipids(includessteroidsandfattyacids)● NucleicAcids● AminoAcids
GROUP1:CarbohydratesMonosaccharides(simplesugars)arethebuildingblocksofcarbohydrates.Theyareliterallyhydratesofcarbon,havingthegeneralformulaCn(H2O)n.Sugarsareburned(oxidized)toreleaseenergyincellularrespirationandtheyplayanimportantroleinhomeostasis.Yourbodymaintainsthelevelofthesugarglucoseinyourbloodwithinaverynarrowrange.Glucoseistheimmediatesourceofenergyforyourcells.Sugarsoccurasringstructures.Therearemonosaccharides(foundassinglerings),disaccharides(foundasdoublerings),andpolysaccharides(3+rings).Wheninaqueoussolution,sugarsfoundassingleringscandynamicallychangefromstraightchainstoringsandbacktostraightchains.Thesamesugarmoleculeshowninringandstraightchainformisshownbelow.Noticethateverycarbonhasanoxygenattachedtoit.
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
3
Itshouldalsobenotedthatglucosecanbefoundasanisomer.Anisomerisacompoundthathasthesamechemicalformulabutadifferentphysicalstructure.Alsonoticethatthecarbonatomsarenumberedinthemoeculesabove.Thiswillbecomeimportantwhenwelearnaboutnucleicacidstructureandfunction.
Sugarscanbejoinedtogetherinlongchainstoformmacromoleculescalledpolysaccharides.Starch,cellulose,andglycogenareexamplesofpolysaccharides.Starch(inplants)andglycogen(inanimals)areeasilybrokendownintosugarsforenergy.Cellulose,ontheotherhand,whichismadeinplants,canbebrokendownonlybyafeworganismsintheworld(primarilythebacteriainthegutsoftermitesandherbivorousanimalssuchascowsandsheep).Yetallthreetypesofmacromoleculesaremadeoflongchainsofsugar,andcellulosediffersonlybyasmallchangeintheconnectingbondbetweeneachpairofsugars.
DIRECTIONS:1. InyourBILL,createtheheading“Monosaccharides.”2. Underneaththeheading,pastethe8monosaccharidemoleculecardstothepage.3. Finally,createtheheading“Disaccharides”andpastethetwodisaccharidesugarsintoyourBILLunder
thisheading.
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
4
GROUP2:LipidsThereareseveraltypesoflipidsmadeandusedbylivingorganisms,including:
● triglyceridefats,phospholipids&steroidsLipidsareadiversegroupofmoleculesbutalltypesoflipidsshareoneimportantcharacteristic:theyareallhydrophobicandarethusinsolubleinwater.Likecarbohydrates,theyarecomposedofcarbon,hydrogenandoxygenbuttheratiosofeachatomdifferfromthatofcarbohydrates.Thefirstgroupoflipidswe’llexamineisthetriglyceridefats,composedofglycerolandfattyacids.Inyoursetofmoleculecards,youshouldhavesomelonghydrocarbonchainswithacarboxylgroupatoneend.Oneofthedefiningfeaturesofthesehydrocarbonchainsistheabsenceofoxygenexceptinonecarboxylgroupatoneendofthemolecule.Thesehydrocarbonchainsarefattyacids.Alongwithasmall3-carbonmoleculecalledglycerol,fattyacidsarethebuildingblocksofoilsandfats.Therearetwotypesoffattyacidstructuresyoushouldfamiliarizeyourselfwith:saturatedandunsaturated.Thesecondgroupoflipidswe’llexamineisthesteroids.Steroidsareatypeoflipidformedoffourcarbonringsfusedtogether.Lookingatthediagramofcholesterolshownatright,you’reprobablythinking,“Butthere’snocarbonintherings!”Itshouldbenotedthatorganicchemistsuseshortcutswhenrepresentingcomplexstructuresoforganicmolecules,sowhatyouareseeingatrightisaskeletalformulaforcholesterol.Becauseorganicmoleculesincludesomanycarbonatoms,chemistsoftendonotincludetheletterCforcarbon.Inthecholesterolmoleculeabove,thereisacarbonatom(notdrawninmostcases)ateverypointofeachofthefourringsandinthesidechain.Thebondsbetweenthecarbonsareshown.Inallbutonecasethecarbonatomsareconnectedtooneanotherbyasinglebond(onepairofsharedelectrons).Inoneringtherearetwocarbonatomsconnectedbyadoublebond(whichmeanstheyaresharingtwoelectrons).Tofurthersimplifythisdrawing,manyofthehydrogenatomshavenotbeendrawn.However,sinceeachcarbonatomformsfourbonds,itisassumedthatthebondsnotdepictedaretohydrogenatoms.Cholesterolservestwoimportantrolesincells:itisamajorcomponentofcellmembranes,anditalsoservesasthebuildingblockforthehormonestestosterone,cortisolandestrogen.
DIRECTIONS:1. InyourBILL,createtheheading“ExampleLipids:TriglycerideFats”andpastethe4componentsof
triglyceridefatsunderneath.Youshouldalsopastethetwoexamplesoftriglyceridefatshereaswell.2. Identifyeachfattyacidandtriglyceridefataseithersaturatedorunsaturated.3. Next,createtheheading“ExampleLipids:Steroids”andpastethe3steroidmoleculesunderneath.
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
5
GROUP3:NucleicAcidsNucleicacidsincludetwokindsofmolecules,RNA(ribonucleicacid)andDNA(deoxyribonucleicacid),andtheirmonomers,nucleotides.Inmostorganisms,DNAcontainsthegeneticblueprintfortheorganismandisreproducedinitsentiretyinnearlyeverycellofitsbody.RNAhelpstotranslatetheinformationinDNAintotheproductionofthousandsofdifferentkindsofproteins,whichinturncontroldevelopmentoftheorganism.Auniquecharacteristicofthenucleicacidsisthepresenceofanitrogenousbase.Thenitrogenousbasesconsistofsingleordoublerings.Eachringcontainstwonitrogenatoms.DNAcontainsfournitrogenousbases:adenine(A)andguanine(G),eachwithdoublerings,andcytosine(C),andthymine(T),withsinglerings.RNAcontainsthreeofthese,A,G,andC,andafourthbase,uracil(U).Thenitrogenousbasesfoundinnucleicacidsareonlyonecomponentofthemonomersofnucleicacids.Themonomerofnucleicacidsiscalledanucleotideandiscomposedof3things:anitrogenbase,a5-carbonsugar,andaphosphategroup.Thesugarsfoundinnucleotidesaremonosaccharidesugarsknownaspentoses,becausetheyonlyhave5carbonsarrangedinaringshape.
Whenanitrogenousbaseisattachedtoa5-carbonsugar,itisknownasanucleoside.
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
6
Nucleosidescancombinewithone,twoorthreephosphatestoformanucleotide.Thegreaterthenumberofphosphates,thegreatertheenergycontainedinthemolecule.Cyclicadenosinemonophosphate(cAMP),derivedfromATP,isusedasasecondmessengermoleculeinsomecellularsignalingpathways.Adenosinediphosphate(ADP)isanintermediatemoleculethatisphosphorylated(hasaphosphategroupattached)inmanymetabolicpathwaysandisusedtotransferenergybetweenmoleculesinorderforcellstoperformwork.Adeninetriphosphate(ATP)isnotonlyamajorsubunitofDNAandRNA,butalsoisamajorenergycarrierinlivingsystems.Youcanseethatithasanitrogenousbase(adenine),a5-carbonsugar(ribose)andthreephosphategroups.
DIRECTIONS:1. Createtheheading“NitrogenousBases”andpastethe5nitrogenousbasemoleculecardsunderneath.2. Identifyeachaseitherapurineorapyrimidineandlabelthemappropriately.3. Createtheheading“Nucleosides”andpastethe4nucleosidemoleculecardsunderneath.Labelthesugarof
eachaseitherriboseordeoxyribose.4. Createtheheading“Nucleotides”andpastethe3nucleotidemoleculecardsunderneath.Labelthesugarof
eachaseitherriboseordeoxyribose.
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
7
GROUP4:AminoAcidsAminoacidsarethemonomersofproteins,biologicallyimportantmoleculesthatperformamultitudeoffunctionsinorganisms,including:
structuralproteins defense(asinantibodies) transportofmolecules hormones
enzymes receptorproteins contractileproteins storageofaminoacids
Thereare20differentaminoacidsfoundinlivingorganisms,andbecauseofthislargenumberofmonomers,itispossibletohaveanearlyinfinitenumberofpossibleproteinsthatcanbeformed.Proteinsequenceandstructureareencodedforbynucleicacids.TheinformationforthesequenceofeveryproteinyourcellsmakeisfoundintheDNA,andtheRNAinyourcellsisresponsibleforcarryingthatinformationtotheribosomesinthecytoplasm,whereassemblyofaminoacidsintoproteinsoccurs.Thestructureofageneralizedaminoacidisshownatright.Theaminogroupisfoundontheleftsideofthecentralcarbon(alsocalledalphacarbon),andthecarboxylgroupisfoundontherightsideofthecentralcarbon.NotethattheRgroupisvariable--thisiswhythereare20differentaminoacidsinlivingthings.
Whentwoaminoacidsarejoinedtogetherthroughtheprocessofdehydrationsynthesis(awatermoleculeisremovedbyjoiningtwomonomerstogether),theresultingmoleculeiscalledadipeptide:
Finally,whenmultipleaminoacidsarejoinedtogetherbypeptidebondsformedasaresultofdehydrationsynthesis,theresultingmoleculeisknownasapolypeptide.NotethattheN--C--Cbackboneisthehallmarkofproteinmolecules:
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
8
DIRECTIONS:1. InyourBILL,createtheheading“GeneralizedAminoAcid”anddrawthestructureforanaminoacid.Label
theaminogroup,carboxylgroup,centralcarbonandRgroup.2. Nowcreatetheheading“AminoAcids”andpastethe9aminoacidmoleculecardsunderneath.Highlightthe
atomsthatcomprisethebackboneofeachaminoacid.
WhatYouWillTurnIn:TheDeliverableEachstudentwillturninthefollowing:
● Acompletesetofcorrectlyidentifiedandlabeledmoleculecutouts○ Thisincludeslabelingthefunctionalgroupsandmoleculetype
● Acompletedbiomoleculessummarychart● Areflectionoflearning(writtenusingcompletesentences)thatincludesthefollowing:
○ 3thingsyoulearnedaboutbiomoleculestructure○ 2thingsyoulearnedaboutthesimilarityamongthebiologicallyimportantmolecules○ 1thingyoulearnedaboutbiologicallyimportantmoleculesthatyoudidnotknowbeforeparticipatingin
thisactivity
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
9
MoleculeCut-Outs:Usethesetocompletetheactivity.
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
10
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
11
Mr.
Bur
ris: A
P Bi
olog
y
AP Biology: Unit 1: Matter Pod 2: Molecules of Life
Adapted from activities by Kim Foglia and Jennifer Sosnowski by Lee Ferguson, Allen HS
12