MUTANT BEES
Purpose
Tobuildamodelofabeeusingcodedinstructions.
Toidentifythedifferenteffectsthatmutationsmayhave onanorganism(positive,negativeorneutral).
Background
DNAisasetofcodedinstructionsformakingalltheproteinsinourbodies.Ituses4bases,represented byA,T,CandG,tocodealltheinformationcontainedinourDNA.Thereareseveralstepstobreakingthecode.DNAis stuckinthenucleus,thereforeitfirstneedstobewritteninto aformthatcanberead outsidethenucleus:Thisstepiscalledtranscription.Thisnewform,RNA,leavesthenucleuswhereitisreadtomakeproteins.Thisiscalledtranslation.Thecodeisreadin3lettersegments(codons)tocreateaminoacids,thesmallestpartofproteins.
Sometimes mutationsoccurintheDNA.ThesearepermanentchangestotheDNAsequenceandmayhavedifferenteffectsontheorganism. Therearethreemajorkindsofmutations:
Substitution-Usuallyonebaseischangedinthesequence. Thesequencearoundthechangeisthesame.
Insertion-Extrabasesareaddedtothesequence. Thesurroundingsequenceisthesameafterthe
insertionends.
Deletion-Some basesareremoved.Thesurroundingsequenceisthesameaftertheinsertionends.Anexampleofeachkindofmutationfollows.Themutation'simpactonthe sequenceisunderlined.
Original:Substitution:Insertion:Deletion:
AMYGOTHERREDHATAMYGOTHERRODHATAMYGOTHISERREDHATAMYOTHERREDHAT
Inthis activity,youwillbegivencodonsandtheinstructionsthatcorrespondtoeachcodon.Yourtaskistofolloweachsetofinstructiontobuildyourownbee.Beware,yourneighbourmaynothavethesamesetofinstructionsasyou!
Materialsforeachgroup
•Threepipecleanersinthreedifferentcolours(oneeachofyellow,black,andbrown)
•Blackpom-pom
•Googlyeyes(oryoucanmakeyourownbee'seyes)
•Gluegun
•Paper(willbeusedtocreatewings)
•Scissors
·.,
Procedure
Usethesequenceyouaregiventobuildamodelofabee.Startby breakingthecorrectsequencebelowintothreeletterchunks(codons). Thenfind thematchingcodonsintheleftcolumnof thetableandplaceyourinstructionsintotheorderofthecorrectsequence. Beware,theinstructionsinthetablearenotinorder,soyouwillneedthesequencetotellyouwhatsetofinstructionscomenext!
Correctsequence:
GTGTAATGCCCGCAATGGCGTCTAGGG
';,
:..:..
..:.(
Bee#4
.:.::..,.
Procedure
Usethesequenceyouaregiven tobuildamodelofabee.Startbybreakingthecorrectsequencebelowintothreeletterchunks(codons).Thenfindthematchingcodonsintheleftcolumnofthetableandplaceyourinstructionsintotheorderofthecorrectsequence. Beware,theinstructionsinthetablearenotinorder,soyouwillneedthesequencetotellyouwhatsetofinstructionscomenext!
Correctsequence:
ATGTAATGCCCGCAATGGCGTCTA
.,
-
Bee# 3
. ./
Procedure
Usethesequenceyouaregiven tobuildamodelofabee.Startbybreakingthecorrectsequencebelowintothreeletterchunks(codons).Thenfindthematchingcodonsintheleftcolumnofthetableandplaceyourinstructionsintotheorderofthecorrectsequence. Beware,theinstructionsinthe tableareatinorder,soyouwillneedthesequencetotellyouwhatsetofinstructionscomenext!
Correctsequence:
ATGTAATGCCCGCAATGGCGTCGACTAGGG
·.
,·,-
Bee#2
Procedure
Usethesequenceyouaregiventobuildamodelofabee.Startbybreakingthecorrectsequencebelowintothreeletterchunks(codons).Thenfindthematchingcodonsintheleftcolumnofthetableandplaceyourinstructionsintothe orderofthecorrectsequence. Beware,theinstructionsinthetablearenotinorder,soyouwillneedthesequencetotellyouwhatsetofinstructionscomenext!
Correctsequence:
ATGTAATGCCCGCAATGGCGTCTAGGG
'-..
Bee#1
Answer Key!!!!
Bee# / BeeProduct1 / Healthy(wildtype)bee
2 / Anextracodonhasbeeninsertedandthisproducesabeemutantwithtwopairsofantennae(steps#8and9 havebeenchangedtosteps#9and10becauseanextra
CGT has beenaddedintotheDNAsequence).
3 / Thereisadeletionthatproducesabeewithnowings(step#9ismissing.Thereisno
GGGcodon).
4 / ThereisaDNAbasesubstitutionthatresultsinaredandblackbee(instep#1ATGis
-
changedtoGTG).
Note:Thebee#islocatedon thestudentworksheet,below theinstructionchart,ontherightside.
PostActivityDiscussion
•Aftertheactivity,studentscancomparetheirbeeproducts.Tohelpthemdothis,writetheDNAsequencesfromtheproceduralstepsontheboard.
•Then,thestudentscancomparethehealthy(wildtype)DNAsequencestothesequencesfromthesickbeescontainingtheDNAmutations.
•AskstudentstocomparetheDNAsequences.IstheirbeehealthyordoesithaveaDNAmutation?Ifithasamutation,whattypeisit?
•Askstudents topredicttheoutcomesofthemutationtheirbeehas.Isthemutationpositive,negative,orneutral?Willthemutationhave aneffectonthebee'shealth?Havethemexplain theiranswers.
•StudentscanalsodiscusstherelationshipbetweenDNA,genes,andproteins.
•Askstudentstothenextrapolatethisactivityand whattheylearnedtohumanDNA.Do allmutationscausediseaseinhumans?
•Thiswrap-upactivitycanbedoneasadiscussion,oritcanbehandedinasa"ticketoutofthedoor"activity.
OPTIONAL:Glueapieceofpipecleanerontoyourbee'sbacksothatyoucanuseitasahookto hangonyourChristm'astreenextyear.
Tips & Tricks
•Beforeyouintroducethebeebuildingactivity,youmaywanttoreviewbeemorphologywiththeclass.Youcandothiswithamodelorwithanimageofabee.
•Itmayalsobehelpfultobrieflyreview:
Howtheinformation ingenesrelatestoproteins(DNA->RNA->proteins).
Thedifferenttypesofmutations(substitutions vs.additionsvs. deletions).
•Forthisactivity, studentscanworkonbuildingtheirownbeemutantsortheycanworkinpairs.
•Tellstudentsthattheirclassmateswillhavedifferentinstructionsandthatthereismorethanonetypeofbeemutanttobemade.
•Letthestudentsknowthateachstepcorrespondsto aDNAcodon.Someworksheetswillhavealloftheinstructions,whileothersmayhaveamodifiedsteportheymayevenbemissingastep.Thestudentswiththesemodifiedinstructionswillendupbuildingbeemutants.
•Dothefirstbee-buildingstepasaclass.
•Letthestudentsknowthattheywillhavetomaketheirownwings.Theycancutthese outfrompaperandgluethemontothebee'sthorax.
•Letthestudentsknowthattheywillhavetogluetheeyesontothebee'shead.
•Note:realhoneybeeshavetwosetsofwings-frontwingsandhindwings.Inflight,these twosetsofwingshooktogetherandworktogether.Forsimplicity,wewillgiveourbeesonesetof.wings,representingtwosetshookedtogetherforflight.