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Chapter 12
Patterns of Patterns of InheritanceInheritance
2Chapter 12
GeneticsGeneticsField founded by Field founded by Gregor MendelGregor Mendel
Worked with Worked with sweet peasweet pea
Knew nothing of cells, Knew nothing of cells, chromosomes, etc.; also chromosomes, etc.; also interested in math.interested in math.
Was unappreciated by peersWas unappreciated by peers
Work was rediscovered after Work was rediscovered after DarwinDarwin
3Chapter 12
MendelMendel
4Chapter 12Seeds & Flowers of Edible Seeds & Flowers of Edible PeaPea
Intact pea flowerIntact pea flower Flower dissected to showFlower dissected to showreproductive structuresreproductive structures
StamensStamens(male)(male)
produceproducepollenpollen
StamensStamens(male)(male)
produceproducepollenpollen
CarpelCarpel(female)(female)producesproduces
eggseggs
CarpelCarpel(female)(female)producesproduces
eggseggs
5Chapter 12Definitions 1Definitions 1
Must know these!!!Must know these!!!
TraitTrait—A variable characteristic of —A variable characteristic of organismorganism
GeneGene—A segment of chromosomal —A segment of chromosomal DNA controlling a specific traitDNA controlling a specific trait
LocusLocus—Chromosomal position —Chromosomal position where DNA for a specific gene liveswhere DNA for a specific gene lives
GenomeGenome—Refers to all standard loci —Refers to all standard loci for a speciesfor a species
6Chapter 12
Definitions 2Definitions 2Must know these!!!Must know these!!!AllelesAlleles—Different forms of a —Different forms of a genegene
• ““Flower color” is a gene;Flower color” is a gene;• ““Purple” is one flower-color allelePurple” is one flower-color allele• ““White” is another flower-color White” is another flower-color alleleallele
GenotypeGenotype—List of alleles for an —List of alleles for an individual at specific genesindividual at specific genes
• Familiar organisms are diploidFamiliar organisms are diploid• One or two alleles per individualOne or two alleles per individual
7Chapter 12
Definitions 3Definitions 3
HomozygousHomozygous—Maternal & paternal —Maternal & paternal alleles samealleles same
• Father donates purple-flower alleleFather donates purple-flower allele• Mother donates purple-flower alleleMother donates purple-flower allele
HeterozygousHeterozygous—Maternal & —Maternal & paternal alleles differpaternal alleles differ
• Father donates purple-flower alleleFather donates purple-flower allele• Mom donates white-flower alleleMom donates white-flower allele
8Chapter 12
Definitions 4Definitions 4PhenotypePhenotype::
• List of traits exhibited by individualList of traits exhibited by individual• Doesn’t always represent genotypeDoesn’t always represent genotype
DominantDominant—Allele that is —Allele that is expressed 100% in heterozygoteexpressed 100% in heterozygote
RecessiveRecessive—Allele is not expressed —Allele is not expressed in heterozygotein heterozygote
Incomplete dominanceIncomplete dominance——heterozygote displays heterozygote displays intermediate trait intermediate trait
9Chapter 12
11 22 33 44 55 66 77 88 99 10101111121213131414151516161717181819192020212122222323242425252626Loci:Loci:
Genes, Alleles,Genes, Alleles,Loci, and ChromosomesLoci, and Chromosomes
Chromosome from One ParentChromosome from One Parent
Homologous Chromosome from Other ParentHomologous Chromosome from Other Parent
11 22 33 44 55 66 77 88 99 10101111121213131414151516161717181819192020212122222323242425252626Loci:Loci:
M locus has gene
that controls
leaf color. Plant
homozygous for this
gene
D locus has gene
that controls
plant height. Plant
homozygous for this
gene
Bk locus has gene
that controls
fruit shape. Plant
heterozygous for this
gene
10
Chapter 12
Genetic SymbolismGenetic SymbolismOften use initial letter of dominant Often use initial letter of dominant alleleallele
• CapitalCapital letter represents dominant letter represents dominant
• Lower caseLower case of of same lettersame letter represents recessiverepresents recessive
If purple flower dominant to If purple flower dominant to white…white…
• ““P” represents allele for purpleP” represents allele for purple
• ““p” represents allele for whitep” represents allele for white
11
Chapter 12
Foundation GeneticsFoundation Genetics
Mendel’s LawsMendel’s Laws
1.1. Law of DominanceLaw of Dominancea.a.Interaction of the two resultingInteraction of the two resulting
in expression of only onein expression of only one
AaAaDominantDominant RecessiveRecessive
12
Chapter 12II. The foundation of II. The foundation of geneticsgenetics
A - aA - a AA aa
2. Law of Segregation2. Law of Segregation
a. Paired alleles of a gene separate a. Paired alleles of a gene separate
during meiosis resulting in a gameteduring meiosis resulting in a gametethat contains only a single allelethat contains only a single allele
for each gene presentfor each gene present
13
Chapter 12II. The foundation of II. The foundation of geneticsgenetics
3. Law of Independent Assortment3. Law of Independent Assortment
Pairs of alleles (genes) that control Pairs of alleles (genes) that control
different traits segregate independentlydifferent traits segregate independentlyof each other during meiosis of each other during meiosis
(genes) (genes) if the alleles are on separateif the alleles are on separate
chromosomeschromosomes
14
Chapter 12
Independent AssortmentIndependent Assortment
1a - 1b1a - 1b
2a - 2b2a - 2b
3a - 3b3a - 3b
1a1a1b1b2b2b3a3a
2a2a3b3b
15
Chapter 12
Linear order - LinkageLinear order - Linkage
RedAllele, p
RoundAllele, l
PurpleAllele, P
LongAllele, L
Flower colorFlower colorgenegene
Pollen shapePollen shapegenegene
16
Chapter 12
Cross Fertilization of Parents Cross Fertilization of Parents
True-breedingTrue-breedingPurple-floweredPurple-flowered
ParentParent
True-True-breedingbreedingWhite-White-
floweredfloweredParentParent
Cross-FertilizeCross-Fertilize
All Purple-floweredAll Purple-floweredOffspringOffspring
Pollen
Pollen
P P
F1
17
Chapter 12
Self-fertilization of FSelf-fertilization of F22
F1
Self-FertilizeSelf-Fertilize
F2 F2 F2 F2
75% Purple75% Purple25% White25% White
18
Chapter 12
Genotype vs PhenotypeGenotype vs Phenotype
Phenotype is how we look/behavePhenotype is how we look/behave• PurplePurple flowers flowers• WhiteWhite flowers flowers
Genotype is what our genes sayGenotype is what our genes say• White FlowersWhite Flowers / / White FlowersWhite Flowers • White FlowersWhite Flowers / / Purple FlowersPurple Flowers • Purple FlowersPurple Flowers / / Purple FlowersPurple Flowers
19
Chapter 12
Genotype vs Phenotype 2Genotype vs Phenotype 2
GenotypesGenotypes• PP = homozygous for PP = homozygous for purplepurple flower flower• pp = homozygous for pp = homozygous for whitewhite flower flower• Pp = heterozygous for flower colorPp = heterozygous for flower color
Phenotype from genotype:Phenotype from genotype:• PP = PP = purplepurple flower flower• Pp = Pp = purplepurple flower flower• pP = pP = purplepurple flower flower• pp = pp = WhiteWhite flower flower
20
Chapter 12
Genotype - PhenotypeGenotype - Phenotype
21
Chapter 12
Gametes of HomozygotesGametes of Homozygotes
A A A A
Homozygous ParentHomozygous Parent GametesGametes
All gametes identicalAll gametes identicalregarding this generegarding this gene
22
Chapter 12
Gametes of HeterozygotesGametes of Heterozygotes
A a A a
Heterozygous ParentHeterozygous Parent GametesGametes
Gametes 50/50Gametes 50/50regarding this generegarding this gene
23
Chapter 12
pphomozygo
usrecessive
Homozygous DominantHomozygous DominantX Homozygous RecessiveX Homozygous Recessive
P
p
P
p
Purp
le P
are
nt
Purp
le P
are
nt
PPhomozygo
usdominant
Whit
e P
are
nt
Whit
e P
are
nt
spermspermnucleinuclei
eggeggnucleinuclei
spermspermnucleinuclei
eggeggnucleinuclei
24
Chapter 12
Pp
pP
P Sperm + p EggsP Sperm + p Eggssame as p Sperm + P Eggssame as p Sperm + P Eggs
Purp
le F
Purp
le F
11Purp
le F
Purp
le F
11
P p
spermspermnucleusnucleus
eggeggnucleusnucleus
++
p P
eggeggnucleusnucleus
spermspermnucleusnucleus
++
25
Chapter 12
PurplePurplehomozygouhomozygou
ssdominant dominant
(PP)(PP)PurplePurpleheterozygoheterozygo
usus (Pp) (Pp)PurplePurple
heterozygoheterozygousus
(pP) (pP)WhiteWhitehomozygouhomozygou
ssrecessive recessive
(pp)(pp)
Pp X Pp CrossPp X Pp Cross
P
p
p
P
p
P
P
p
++
++
++
++
FF11 Sperm SpermFF11 Eggs Eggs FF22 Offspring Offspring
26
Chapter 12Using Punnett SquaresUsing Punnett Squaresin Genetic Crossesin Genetic Crosses
Named after geneticist Reginald Named after geneticist Reginald PunnettPunnett
Figured using Figured using Punnett squaresPunnett squares• Considers only genes of interestConsiders only genes of interest
• List sperm genotypes across topList sperm genotypes across top
• List egg genotypes down sideList egg genotypes down side
• Fill in boxes with zygote genotypesFill in boxes with zygote genotypes
27
Chapter 12
P p
1(25%)White
3 (75%)3 (75%)PurplePurple
FrequenciesFrequenciesPhenotypesPhenotypes
GenotypesGenotypes
FrequenciesFrequencies
Making a Punnett Square:Making a Punnett Square:Heterozygous X HeterozygousHeterozygous X Heterozygous
Eggs of Heterozygous Eggs of Heterozygous PlantPlant
Pollen ofPollen ofHeterozygous Heterozygous
Plant Plant
1111 22
P
p pP
PpPP
pp
PP pppP Pp
28
Chapter 12
ProbabilityProbability
29
Chapter 12
ProbabilityProbabilityProbabilityProbability
Coin TossCoin Toss Probability of Probability of heads =heads = 1/2 or 50%1/2 or 50%
Probability of tails =Probability of tails =1/2 or 50%1/2 or 50%
10 tosses - 7th toss = heads10 tosses - 7th toss = heads
10 tosses - 4th toss = heads10 tosses - 4th toss = heads
10 tosses - 3rd toss = tails10 tosses - 3rd toss = tails
1/21/2
1/21/2
1/21/2
3 tosses in a row = heads3 tosses in a row = heads 1/81/8
1/2 (1st toss) X 1/2 (2nd toss) X 1/2 (3rd toss)1/2 (1st toss) X 1/2 (2nd toss) X 1/2 (3rd toss)
30
Chapter 12
Consider Flower ColorConsider Flower ColorPretend flower color affected by Pretend flower color affected by only one gene (only one gene (monohybrid monohybrid crosscross))
Assume all alleles are purple or Assume all alleles are purple or whitewhite
Purple (P) is dominant to white (p)Purple (P) is dominant to white (p)
HeterozygotesHeterozygotes will have flowers as will have flowers as purple as homozygous dominantspurple as homozygous dominants
31
Chapter 12
p p
(50%)White
(50%)(50%)PurplePurple
FrequenciesFrequenciesPhenotypesPhenotypes
GenotypesGenotypes
FrequenciesFrequencies
Test Cross:Test Cross:Heterozygous X Homozygous Heterozygous X Homozygous RecessiveRecessiveEggs of Homozygous Eggs of Homozygous
RecessiveRecessive
Pollen of unknownPollen of unknownplant with dominant plant with dominant
phenotypephenotype(Heterozygous)(Heterozygous)
22
P
p pp
PpPp
pp
Pp pppP pp22
32
Chapter 12
p p
(100%)(100%)PurplePurple
FrequenciesFrequenciesPhenotypesPhenotypes
GenotypesGenotypes
FrequenciesFrequencies
Test Cross:Test Cross:Homozygous X Homozygous Homozygous X Homozygous RecessiveRecessive
Eggs of Homozygous Eggs of Homozygous RecessiveRecessive
Pollen of unknownPollen of unknownplant with dominant plant with dominant
phenotypephenotype(Homozygous)(Homozygous)
P
Pp
PpPp
Pp
Pp PpPp Pp
P
44
33
Chapter 12Traits of PeasTraits of PeasStudied by MendelStudied by Mendel
Plant size
Flower location
Flower color
Pod color
Pod shape
Seed shape
Seed color
34
Chapter 12Dihybrid Cross:Dihybrid Cross:SSssYYyy X S X SssYYyy
SYSY
SSyy
ssYY
sysy
SsYy ParentSsYy ParentSelf-fertilizesSelf-fertilizes
14
14
14
14
SYSY SSyy ssYY sysy14
14
14
14
Eggs
Sperm
116
116
116
116
116
116
116
116
116
116
116
116
116
116
116
116
SSYYSSYY SSYSSYyy SSssYYYY SSssYYyy
SSSSyyYY SSSSyyyy SSsysyYY SSsyysyy
ssSYYSYY ssSYSYyy ssssYYYY ssssYYyy
ssSSyyYY ssSSyyyy ssyssyYY ssyyssyy
35
Chapter 12
Dihybrid Cross - ProbabilityDihybrid Cross - Probability
B = Brown EyesB = Brown Eyesb = Blue Eyesb = Blue Eyes
A = Black HairA = Black Hair
a = Blond Haira = Blond Hair
P GenerationP Generation
BbAa BbAa BbAaBbAa
Possible GametesPossible Gametes
MaleMaleFemaleFemale
malemaleBA,Ba,bA,BA,Ba,bA,
babaFemaleFemale
BA, Ba, bA, baBA, Ba, bA, ba
36
Chapter 12
Dihybrid ProbabilityDihybrid Probability
ABAB AbAb aBaB abab
ABAB
AbAb
aBaB
abab
ABAABABB AABbAABb AaBAaB
BB AaBbAaBb
AABbAABb AAbbAAbb AaBbAaBb AabbAabb
AaBBAaBB AaBbAaBb aaBBaaBB aaBbaaBb
AaBbAaBb AabbAabb aaBbaaBb aabbaabbBlack Hair - Brown eyesBlack Hair - Brown eyesBlack Hair - Blue EyesBlack Hair - Blue Eyes
9933Blond Hair - Brown Eyes Blond Hair - Brown Eyes Blond Hair - Blue EyesBlond Hair - Blue Eyes
3311
37
Chapter 12Dihybrid Probability - Math Dihybrid Probability - Math SolvedSolved
Brown Eyes = BBrown Eyes = B
Blue Eyes = bBlue Eyes = b
Black Hair = ABlack Hair = A
Blond Hair = aBlond Hair = a
Male BbAaMale BbAa
Female BbAaFemale BbAa
Probability = 3/4Probability = 3/4
Probability = 1/4Probability = 1/4
Probability = 3/4Probability = 3/4
Probability = 1/4Probability = 1/4
38
Chapter 12Dihybrid Probability - Math Dihybrid Probability - Math SolvedSolved
3/4 B-3/4 B-1/4 bb1/4 bb
3/4 A -3/4 A -1/4 aa1/4 aaXX
9/16 B-A-9/16 B-A-3/16 bbA-3/16 bbA-3/16 B-aa3/16 B-aa1/16 bbaa1/16 bbaa
39
Chapter 12
LinkageLinkage
RedAllele, p
RoundAllele, l
PurpleAllele, P
LongAllele, L
Flower colorFlower colorgenegene
Pollen shapePollen shapegenegene
40
Chapter 12
Incomplete DominanceIncomplete Dominance
41
Chapter 12
Incomplete DominanceIncomplete Dominance
42
Chapter 12
RR RR
(100%)(100%)Pink (intermediate)Pink (intermediate)
FrequenciesFrequenciesPhenotypesPhenotypes
GenotypesGenotypes
FrequenciesFrequencies
Incomplete Dominance:Incomplete Dominance:Homozygous-X Homo RecessiveHomozygous-X Homo RecessiveEggs of HomozygousEggs of Homozygous
RR Red Parent Red Parent
Pollen ofPollen ofHomozygous Homozygous
R'R' White White ParentParent
R'
R'R'R
R'RR'R
R'R
R'R R'RR'R R'R
Pink Pink
Pink Pink
11
43
Chapter 12
(25%)(25%)(25%)(25%)RedRed WhiteWhite
RR R'R'
(50%)(50%)PinkPink
FrequenciesFrequenciesPhenotypesPhenotypes
GenotypesGenotypes
FrequenciesFrequencies
Incomplete Dominance:Incomplete Dominance:FF11 X F X F11
Eggs of HeterozygousEggs of HeterozygousRR' Pink FPink F11 Parent Parent
Pollen ofPollen ofHeterozygous Heterozygous
RR' Pink F Pink F11 ParentParent
RR
R'R'R'R
RR'RR
R'R'
RR R'R'RR' R'R1111 22
Red Pink
Pink White
44
Chapter 12Normal Red Blood Cells - Normal Red Blood Cells - PleiotropyPleiotropy
45
Chapter 12
Sickled Cells - PleiotropySickled Cells - Pleiotropy
46
Chapter 12
PleiotropyPleiotropy
47
Chapter 12Epistasis two sets of genes Epistasis two sets of genes working togetherworking together
48
Chapter 12Polygenic Inhertance - Polygenic Inhertance - multiple genesmultiple genes
Three Sets of GenesThree Sets of Genes
Working in tandemWorking in tandem
AABBCCAABBCC
AaBbCcAaBbCc
aabbccaabbcc
Skin ColorSkin Color
HeightHeight
Eye ColorEye Color
49
Chapter 12Polygenic Inhertance - Polygenic Inhertance - multiple genesmultiple genes
50
Chapter 12
ABAB
AbAb
aBaB
abab
ABAB AbAb aBaB abab
HumaHuman Eye n Eye ColorColor
EGGSEGGS
SPER
MS
PER
M
MotherMother
AaBbAaBb
FatherFather
AaBbAaBb
AABBAABB AABbAABb AaBBAaBB AaBbAaBb
blackblack dark browndark brown dark browndark brown light brownlight brown
AAbBAAbB
dark browndark brown
AAbbAAbb
light brownlight brown
AabBAabB
light brownlight brown
AabbAabb
blueblue
aABBaABB aABbaABb aaBBaaBB aaBbaaBb
dark browndark brown light brownlight brown light brownlight brown blueblue
aABbaABb aAbbaAbb aaBbaaBb aabbaabb
light brownlight brown blueblue blueblue light bluelight blue
51
Chapter 12
Multiple AllelesMultiple Alleles
Blood TypeBlood Type A - B - AB - OA - B - AB - O
A A AA - AoAA - Ao
BB BB - BoBB - Bo
ABAB ABAB
OO oooo
GenotypeGenotype
52
Chapter 12
10%10%
34%34%
37%37%
4%4%
B or ABB or AB
A or ABA or AB
O,AB,O,AB,A,BA,B
(universal(universal))
ABAB
B or OB or O
A or OA or O
OO
AB, A,AB, A,B, OB, O
(universal)(universal)
AA
BB
A & BA & B
NeitherNeither
BB or BOBB or BO
AA or AOAA or AO
OOOO
ABAB
OO
ABAB
BB
AA
FreqFreqDonatesDonatesRe-Re-ceivesceives
Anti-Anti-bodiesbodiesRBCsRBCsGenotypeGenotypeTypTyp
ee
Human ABO Blood GroupHuman ABO Blood Group
53
Chapter 12
RH Blood FactorRH Blood Factor
RH - another Blood ProteinRH - another Blood Protein
Rh + you have the proteinRh + you have the protein
Rh -- you donot have the proteinRh -- you donot have the protein85% of the population are Rh +85% of the population are Rh +
15% of the population are Rh 15% of the population are Rh −−
4% of the population are AB4% of the population are AB
What % of the population are AB What % of the population are AB −−
54
Chapter 12
Rh Blood FactorRh Blood Factor
Female Rh + Female Rh + Male Rh Male Rh −−
Child Rh +Child Rh +
Female Rh Female Rh −− Male Rh Male Rh
Child Rh Child Rh Mother will start to build upMother will start to build up
anti Rh antibodiesanti Rh antibodies
55
Chapter 12
XX11 XX22
Sex DeterminationSex Determinationin Mammalsin Mammals
EGGSEGGS
Male ParentMale ParentYYXXmm
SSPPEERRMM
Female OffspringFemale Offspring
Male OffspringMale OffspringYY
XXmmXXmmXX11 XX22XXmm
YY YYXX11 XX22
XX11 XX22Female ParentFemale Parent
56
Chapter 12Sex Determination Sex Determination in Mammalsin Mammals
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
57
Chapter 12
Sex Linked Sex Linked
The gene is found on the X chromosomeThe gene is found on the X chromosomeColor Blindness - recessive Color Blindness - recessive
traittraitFemale possible genotypesFemale possible genotypes
CCCC CcCc cccc
Male possible genotypesMale possible genotypes
CyCy cycy
58
Chapter 12
Color BlindnessColor Blindness
59
Chapter 12
Sex LinkedSex Linked
GenotypesGenotypes Cc - CyCc - Cy
CC cc
CC
yy
CcCc CcCc
CyCy ccyy
25% colorblind25% colorblind50% of the males colorblind50% of the males colorblind
60
Chapter 12
Sex InfluencedSex Influenced
Dominant in one sexDominant in one sex
Recessive in the otherRecessive in the other
Reason: Reason:
The presence or absenceThe presence or absence
TestosteroneTestosteroneEstrogenEstrogen
of the sex hormonesof the sex hormones
61
Chapter 12Sex InfluencedSex InfluencedMale Pattern BaldnessMale Pattern Baldness
62
Chapter 12Sex Influenced Sex Influenced Male Pattern BaldnessMale Pattern Baldness
Dominant in MalesDominant in MalesRecessive in FemalesRecessive in Females
BBBB
BbBb
bbbb
BaldBaldBalBaldd
NonbaldNonbald
BaldBald
NonbaldNonbald
NonbaldNonbald
63
Chapter 12
Sex Limited TraitSex Limited Trait
Trait is limited to one sexTrait is limited to one sex
All secondary sex characteristics All secondary sex characteristics
are sex limitedare sex limited
64
Chapter 12
Sex Limited TraitSex Limited Trait
Cabbage ButterflyCabbage Butterfly
YellowYellow
Cabbage ButterflyCabbage Butterfly
whitewhite
65
Chapter 12
Sex Limited TraitSex Limited Trait
66
Chapter 12
Sex Limited TraitSex Limited Trait
67
Chapter 12
Sex Limited TraitSex Limited Trait
68
Chapter 12
How to Read PedigreesHow to Read Pedigrees
= male= male = female= female
= parents= parents
oror = individual who shows the trait = individual who shows the trait
oror = heterozygous carrier of= heterozygous carrier ofautosomal trait autosomal trait
= offspring = offspring
11 22 33I, II, III, IV, or VI, II, III, IV, or V = generation = generation
69
Chapter 12
A Recessive PedigreeA Recessive Pedigree
70
Chapter 12Pedigrees:Pedigrees:Legacy of Queen VictoriaLegacy of Queen Victoria
71
Chapter 12Incidence of Down Incidence of Down SyndromeSyndrome
1010 2020 3030 4040 505000
100100
200200
300300
400400
Age of Mother (years)Age of Mother (years)
Num
ber
per
100
0 B
irth
sN
um
ber
per
100
0 B
irth
s
Chapter 12
The endThe end
73
Chapter 12
Meiosis IIMeiosis I
YYSS
SS YY
yyss
ss yy
yySS
SS yy
YYss
YYss
SS yy yySS
YY YYssss
Independent AssortmentIndependent Assortment
SSss
YYyy
SS
ss
YY
yy
YY
yy
SS
ss
YY YY
SS
ss
yy yySS
ss
Randomly one or the
other
SS YY YYSS
ss yy yyss
ChromosomeReplication
74
Chapter 12
red
red
Purple
Purple
round
round
Long
Long
PP
PP
pp
pp
LL
LL
ll
ll
PP
pp
pp
LL
LL
ll
ll
PP
LL
pp LL
ll
ll
PP
pp
PP
LL
pp LL
ll
ll
PP
pp
LL
LL
ll
ll
PP
PP
pp
pp
PP
PP
pp
pp
LL
LL
ll
ll
PP
pp
pp
LL
LL
ll
ll
Crossing OverCrossing Over
SisterSisterChromatidsChromatids
DuplicatedDuplicatedChromosomeChromosome
DuplicatedDuplicatedChromosomeChromosome
LL
LL
ll
ll
PP
PP
pp
pp
SisterSisterChromatidsChromatids
Hom
olo
gous
Hom
olo
gous
Chro
moso
mes
Chro
moso
mes
PP
PP
pp
pp
LL
LL
ll
ll
PP
pp
pp
LL
LL
ll
ll
pp LL
PP ll
LLPP
llpp
old combinationold combination
new combinationnew combination
new combinationnew combination
old combinationold combination
FlowerColor
PollenShape
75
Chapter 12
25%25%Normal fNormal f Carrier fCarrier fNormal mNormal m
25%25% 25%25% 25%White-e m
FrequenciesFrequenciesPhenotypesPhenotypes
GenotypesGenotypes
FrequenciesFrequencies
Sex Linkage:Sex Linkage:Eye Color in Fruit FliesEye Color in Fruit Flies
Eggs of Eggs of XR Xr FemaleFemale
Sperm ofSperm ofXXRRY Male Y Male
1111
YXR
XRXrXRXR
YXr
XRXR XrYXRXr XRY
R r
R
Female Female
Male Male
11 11
