Download Patterns of Gene Inheritance

Cell Biology Student Outline – Patterns of Gene Inheritance
Patterns of Gene Inheritance
1.
2.
3.
Introduction
A.
Homologous Chromosomes
i.
Alleles
•
Loci
ii.
Somatic Cells
iii.
Gametes
a.
Segregation
Dominant and Recessive Alleles
A.
Genotype
i.
Homozygous – WW or ww
ii.
Heterozygous - Ww
B.
Phenotype
One-Trait Crosses
A.
Monohybrids
B.
Parental Generation (P)
C.
Filial Generation (F)
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Cell Biology Student Outline – Patterns of Gene Inheritance
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Cell Biology Student Outline – Patterns of Gene Inheritance
D.
Punnet Square
Phenotype ratio is 3:1
E.
Genotype ratio is 1:2:1
Probability
R = 1/2
r = 1/2
Chance of RR = 1/2 x 1/2 = 1/4
Chance of Rr = 1/2 x 1/2 = 1/4
Chance of rR = 1/2 x 1/2 = 1/4
Chance of rr = 1/2 x 1/2 = 1/4
1/4 + 1/4 + 1/4 = 3/4 = 75%
F.
Recessive trait - 1/4 or 25%
Testcross
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Cell Biology Student Outline – Patterns of Gene Inheritance
4.
Segregation and Independent Assortment
Figure 23.6 Text. and diagram
5.
Two Trait Crosses
•
Dihybrid Cross
A.
Two Trait Test Cross
See Figure 23.8
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Cell Biology Student Outline – Patterns of Gene Inheritance
6.
7.
8.
9.
10.
11.
Genetic Disorders
A.
Autosomal Dominant Disease
i.
AA or Aa
B.
Recessive Disease
i.
aa
C.
Pedigree Chart
Autosomal Dominant Diseases
A.
Neurofibromatosis
B.
Huntington Disease
Autosomal Recessive Diseases
A.
Tay-Sachs Disease
B.
Cystic Fibrosis
C.
Phenylketonuria
Polygenic Inheritance
A.
Skin Color
Blood Types
Phenotype
Genotype Possibilities
A
AA, AO
B
BB, BO
AB
AB
0
OO
•
Co-dominance
Incomplete Dominance
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Cell Biology Student Outline – Patterns of Gene Inheritance
A.
Sickle-Cell Disease
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