Mrs. Sharp's classes



Science 10 – GeneticsNon-Mendelian Genetics-Mendel’s peas were very simple, all the traits he looked at were either dominant or recessive-many humans traits are not this simpleex. Humans can be a range of heights, not just tall or short-typically, a dominant allele always masks the recessive allele-not always the case!Incomplete Dominance-sometimes the dominant allele does not completely mask the recessive allele-results in a third phenotype that is a mixture of the parents (blending!)1002773-14241Example: Black is incompletely dominant over white, if you crossed a black squirrel (BB) with a white squirrel (bb), what percentage of the offspring would be gray?43169334957942136133697939490136433939612538305936523732041936617336001934759734129935094535461948257312859495173535391459973301391455653-1558113588136469912418137837912050934561910754939529910837733589989549311545989477374419681293-91017050531249914736537534914239739046914088539910912756537822911129331372693856133952743885653110394594173-4872690953332994899093-13446735293-796863444653-586813463373-55441379529313139932920131267191545293-342011442333-97211333613118791202213183599941338783998873350399793973-158841328796035332951952039737760952360131010095056373118649480689310172939504538012938269738300938518138732934032538588934284531132496452093-734666375053-15146633365357346199013140146143573104146025853168945952413-493465695373-435865529413-623065570813-428665359493399344890413-475463552653-695063122813-5798633280131108543791333-2149463385973-2606663322613-2217863972413483393857213825393885293936993610973-731313478853-587313511613-328113180413-44691144485323334614812132041861481213225786Example: Red is incompletely dominant over white, cross a homozygous red flower and a homozygous white flower. What percentage of the offspring will look like their parents?4383893199664285973343664071053498464070693660463717173-27194373805359263589013-10274359009370061622693-142341512173566861432253570461273853761261278893368861065773-469941090973-17834888293-39434926813134861771013625711595693996511288973164811929333805711633493-426991564373-340591418573-2793914556532390112655733542110852134461932933-556596264533155426576341315542657490137910653047731262664221893-566144231613-450943940373-260143946493-22541748333-454541704053926616918132726616615736146615380931106613472936902612061731377861215173873861030853744269268138378664574932191633185314716280733252316155093169516011453-3209602549321915874653-100495815973-820495713733-111295624093-50095410613572715233853-626095003813-3452941747337599141938131047913783773-1760962551739961612881362881601433360001590669324015670893-5879559061311041551753327615532653664815244653481214275893-213593932093344413812933-321593836693-217193632213301214471013-2096396369653874866292973568866271373110886596465355446588257362646584729310260655718938964654206935112653674135616653443731072865214773428464169333806463706373219664114613-3340743748493-296274591749384456588293313053651276531114564282733-275044194533-60984396737356163823733-555843852173-213843578573156966258413694616012173-561795549213-417795447333-392595270933-316995178773-4699Codominance-sometimes both alleles are dominant, resulting in both alleles showing when they are both present2922293-42423509993341477748997734514974534733438897Example: The alleles for red and white petals are codominant in flowers. Heterozygous flowers have white petals with red dots. If we crossed a white flower and a red flower what percentage of the offspring would have white petals with red dots?4759733-326034761173-203634568573-700434392893-783234426373-509631947053-863318307735364717605737128715395331508471544213979271260533-1907312745733744710693733607106001350767216197393372213461313045220928531254121942373750125161493-253035184533-44234854413337374870973744171762373-8231547453744171569053362571267733-44231047413-127036221333965874668293113507322217394673173573-12493312425318467305261337547292301337072733293328672615573749872547893854272447813767872399213980272164853775072123093108827209861399827197369381827181133313222715636531610276319613927526167693-735686018293-202885890493-76885833253-1380851906536503250837334055250963334451248223739311247093336791243122531175921544573203921252613-303681093493-606081110773-41888651077318357645389336357634229345717620657314376058973-172835987693-151235955653-25235933693248375759813399574724093-6516346686531339175407013-2512836593213236076483773-24633640133348807623933316476024773250475925413675275839013621275218733714875122253628475143493988475064293-4278334660373-36663362544535073262191731133726190013928526053573770125785013489324792133-662684675853-770684698893-471884355453-529486342293966626269933631825893013-336585684573-5885847190531826514733417076124133-281336051053-716936003893-112135898773-133735760173307579869310275784293-13373Example: Humans have 4 blood types, A, B, AB, and O. The alleles for A and B are codominant. The O phenotype results from having no A or B allele (homozygous recessive). If you had O-blood and you had children with someone who had AB-blood. What would the blood types of your children be? Give your answer as genotypic and phenotypic ratios.1956053-309781831493377821731053269821675973-212581547813-259381243613-252181257653-241381105373493021126253-4753880693310186279649340302606773-54378625853-2953844513358302438653-7741861482531703876046013163187515321373074634453191876294773152872618497314567261482531089525980133671258631331391258850932111236629340912388253-188482219331409929305313055284773-379281983053-22088185669366112172961359272166805314632151793392321191413891521179533-3900886885310175285121357112675893107152677333-3828849589369712500933-314486565493540826440933249226338693324826082733105225929013324825936213980025526533-247598527777311276250729331055625124413-920785094893-10683844659731055624473173-5535846636131494824486853893624479293-816384047293483224039013-7587845305399082199313332482190781312680217872131289621719173918821578413756821211573771229721731541624246733549274897253-4040734174733-4519534336373-423513419213-318332838538012789453-63513138773-116731221653-3975396821322887710453-48033729893-35073540173-55593560693-1599366166131216526528773106892645569317277263458931068926345893121652625805370532616301377732611189399692596537392492599489370532445085348572204569316017268581732322267483731262663137384626258053232225636333-2183385307293815425080493-1085385060693-1304984604933595824448693-1013384000133-959384030013-203383340253-646183194093-170983090773437422975573390622926253-152982815733-278982560493-34182420093-4733822170531262216881317822209609313142204893333302189017366621739333198216028931998214934531422213361331026212533332718297541382982979013343827097334446253009343382Lethal Alleles-it is possible that certain combinations of alleles can have negative effects and can even be lethalExample: In mice, the allele that codes for yellow and brown coloration can also produce a lethal combination that, when present, causes a defect and the mouse never grows to maturity. Yellow is dominant and brown is recessive but a homozygous dominant results in a lethal combination. If you crossed two heterozygous yellow mice, what would the genotypic and phenotypic ratio of the offspring be? ................
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