27. Figure 14.5-2
P Generation
Appearance:
Purple flowers White flowers
Genetic makeup:
pp
PP
p
Gametes:
P
F1 Generation
Appearance:
Genetic makeup:
Gametes:
Purple flowers
Pp
1
1
/2 p
/2 P
28. Figure 14.5-3
P Generation
Appearance:
Purple flowers White flowers
Genetic makeup:
pp
PP
p
Gametes:
P
F1 Generation
Appearance:
Genetic makeup:
Gametes:
Purple flowers
Pp
1
1
/2 p
/2 P
Sperm from F1 (Pp) plant
F2 Generation
Eggs from
F1 (Pp) plant
P
p
PP
Pp
Pp
pp
P
p
3
:1
33. Figure 14.7
TECHNIQUE
Dominant phenotype,
unknown genotype:
PP or Pp?
Predictions
If purple-flowered
parent is PP
Sperm
p
p
Recessive phenotype,
known genotype:
pp
P
P
Pp
Eggs
If purple-flowered
parent is Pp
Sperm
p
p
or
Pp
Pp
P
Pp
pp
Eggs
pp
p
Pp
Pp
RESULTS
or
All offspring purple
/2 offspring purple and
1
/2 offspring white
1
36. Figure 14.8
EXPERIMENT
YYRR
P Generation
yyrr
Gametes YR
yr
F1 Generation
Predictions
YyRr
Hypothesis of
dependent assortment
Hypothesis of
independent assortment
Sperm
or
Predicted
offspring of
F2 generation
/4 YR
1
Sperm
/2 yr
/2 YR
/4 Yr
1
1
/4 yR
/4 yr
1
1
1
1
/4 YR
YYRR
YYRr
YyRR
YyRr
YYRr
YYrr
YyRr
Yyrr
YyRR
YyRr
yyRR
yyRr
YyRr
Yyrr
yyRr
yyrr
/2 YR
1
YyRr
YYRR
Eggs
1
/4 Yr
Eggs
/2 yr
1
YyRr
/4
yyrr
1
/4 yR
/4
3
1
1
Phenotypic ratio 3:1
/4 yr
9
/16
/16
3
3
/16
/16
1
Phenotypic ratio 9:3:3:1
RESULTS
315
108
101
32
Phenotypic ratio approximately 9:3:3:1
40. Figure 14.9
×
Rr
Segregation of
alleles into eggs
Rr
Segregation of
alleles into sperm
Sperm
/2
1
R
/2
/4
Eggs
1
r
/2
r
R
R
1
1
r
R
R
1
/2
1
/4
r
r
R
r
/4
1
/4
1
56. Figure 14.11
(a) The three alleles for the ABO blood groups and their
carbohydrates
Allele
Carbohydrate
IA
IB
i
none
B
A
(b) Blood group genotypes and phenotypes
Genotype
IAIA or IAi
IBIB or IBi
IAIB
ii
A
B
AB
O
Red blood cell
appearance
Phenotype
(blood group)
97. Figure 14.UN03
Relationship among
alleles of a single gene
Complete dominance
of one allele
Description
Heterozygous phenotype
same as that of homozygous dominant
Incomplete dominance Heterozygous phenotype
intermediate between
of either allele
the two homozygous
phenotypes
Codominance
Both phenotypes
expressed in
heterozygotes
Example
PP
Pp
CRCR CRCW CWCW
IAIB
Multiple alleles
In the whole population, ABO blood group alleles
some genes have more
IA, IB, i
than two alleles
Pleiotropy
One gene is able to affect Sickle-cell disease
multiple phenotypic
characters
98. Figure 14.UN04
Relationship among
two or more genes
Epistasis
Description
The phenotypic
expression of one
gene affects that
of another
Example
BbEe
BE
BbEe
bE
Be
be
BE
bE
Be
be
9
Polygenic inheritance
A single phenotypic
character is affected
by two or more genes
AaBbCc
:3
:4
AaBbCc