Chromatin in a Normal Cell(one length from each parent)Chromatin in a Normal Cell(one length from each parent)
AlleleAllele
A version of a geneA version of a gene
DominantDominant
Allele that may mask thepresence of anotherAllele that may mask thepresence of another
RecessiveRecessive
Allele that may be maskedby anotherAllele that may be maskedby another
HeterozygousHeterozygous
The 2 alleles are differentThe 2 alleles are different
HomozygousHomozygous
The 2 alleles are identicalThe 2 alleles are identical
Earlobe GeneEarlobe Gene
Melanin GeneMelanin Gene
Polydactyly GenePolydactyly Gene
FF
FreeFree
ff
AttachedAttached
aa
AlbinoAlbino
aa
albinoalbino
PP
ExtraExtra
FingersFingers
PP
ExtraExtra
FingersFingers
♂♂
♀♀
Chromatin in a Normal Cell(one length from each parent)Chromatin in a Normal Cell(one length from each parent)
GenotypeGenotype
The set of alleles anorganism possessesThe set of alleles anorganism possesses
PhenotypePhenotype
The genetic outcomeresulting from the genotypeThe genetic outcomeresulting from the genotype
Earlobe GeneEarlobe Gene
Melanin GeneMelanin Gene
Polydactyly GenePolydactyly Gene
FF
FreeFree
ff
attachedattached
aa
albinoalbino
aa
albinoalbino
PP
ExtraExtra
FingersFingers
PP
ExtraExtra
FingersFingers
♂♂
♀♀
InheritanceInheritance
F
f
F
f
f
f
F
F
f
f
F
F
Exact copiesExact copies
Pure bred parents
What will the F1 offspring look like?
PP x pp
p
p
P
P
P
p
Phenotype = 100% Purple
Genotype = 100% Heterozygous
What will the F2 offspring look like?
Phenotype = 75% Purple 25% white
Genotype = 100% Homo. Dominant,50% Hetero., 25% Homo. Recessive
Dihybrid CrossDihybrid Cross
GgYyGgYy
GYGY
PHENOTYPEPHENOTYPE
G-Y- : 9G-Y- : 9
G-yy : 3G-yy : 3
ggY- : 3ggY- : 3
ggyy : 1ggyy : 1
GyGy
gYgY
gygy
GGYYGGYY
GGYyGGYy
GgYYGgYY
GgYyGgYy
GYGY
ggYYggYY
GgYyGgYy
GgyyGgyy
GgYYGgYY
GgYyGgYy
GGyyGGyy
ggYyggYy
GGYyGGYy
GyGy
gYgY
GgYyGgYy
GgyyGgyy
ggYyggYy
ggyyggyy
gygy
Law of segregation: twoalleles for a trait separatewhen gametes are formedLaw of segregation: twoalleles for a trait separatewhen gametes are formed
Law of Independentassortment:Law of Independentassortment:
Alleles of different genesseparate independently ofone another duringgamete formationAlleles of different genesseparate independently ofone another duringgamete formation
CodominanceCodominance
Both alleles are detectable in a specimenBoth alleles are detectable in a specimen
Gene:Cattle coat colorGene:Cattle coat color
AllelesAlleles
CR= redCR= red
CW= WhiteCW= White
GenotypesGenotypes
CRCR = red coatCRCR = red coat
CWCW= white coatCWCW= white coat
CRCW= roan coatCRCW= roan coat
Multiple AllelesMultiple Alleles
More than two alleles exist for a geneMore than two alleles exist for a gene
Human Blood TypeHuman Blood Type
IA= Type A carbs on RBC surfaceIA= Type A carbs on RBC surface
IB= Type B carbs on RBC surfaceIB= Type B carbs on RBC surface
i= Neither type on RBC surfacei= Neither type on RBC surface
Multiple AllelesMultiple Alleles
Blood TypeBlood Type
GenotypeGenotype
AntibodiesAntibodies
Universal AcceptorUniversal Acceptor
Universal DonorUniversal Donor
Linked GenesLinked Genes
Sex linked: traits are tied to X or YSex linked: traits are tied to X or Y
Xr
Y
XR
XR
XR
XR
XR
XR
Xr
Xr
Y
Y
XR
Y
Xr
XR
XR
XR
XR
Xr
Xr
XR
Y
Y
Sex linked: traits are tied to X or YSex linked: traits are tied to X or Y
Xr
Y
XR
XR
XR
XR
XR
XR
Xr
Xr
Y
Y
XR
Y
Xr
XR
XR
XR
XR
Xr
Xr
XR
Y
Y
Color blindness:males
Recessive x linked
Abnormal productionof pigment(protein)
Does not absorb redgreen light
Sex influencedSex influenced
Trait not tied to sex chromosomeTrait not tied to sex chromosome
Autosomal chromosome produces protein whichaffects the production of other proteins.Autosomal chromosome produces protein whichaffects the production of other proteins.
Testosterone affectsTestosterone affects
the production andthe production and
location of hair in males.location of hair in males.
Patterns of InheritancePatterns of Inheritance
Polygenic: Eye color, skin color, heightPolygenic: Eye color, skin color, height
Complex characters: Skin color=sun,Complex characters: Skin color=sun,
Multiple alleles: Blood typeMultiple alleles: Blood type
Incomplete Dominance: Red x White= PinkIncomplete Dominance: Red x White= Pink
X-linked: Color blindness, fruit fly eyesX-linked: Color blindness, fruit fly eyes
Sex influenced: Male pattern baldnessSex influenced: Male pattern baldness
Single alleles: Huntington’s disease,Single alleles: Huntington’s disease,