lectures posted online after lecture. textbook sections and/or pages posted a few days prior to each...
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Lectures posted online after lecture.
Textbook sections and/or pages posted a few days prior to each lecture.
In many instances there is a unique pattern of inheritance.
Traits disappear and reappear in new ratios.
CB 14.3
Genotype PhenotypeCB 14.6
Human blood types
AA orAO
AB
BB orBO
OO
CB tbl 14.2
Looking at the past:
If Frank has B blood type,
his Dad has A blood type,
And his Mom has B blood type…
Should Frank be worried?
Mom=B blood
BB or BO
Dad=A blood
AA or AO
Gametes all B / 50% B and50% O
all A / 50% A and50% O
possible
genotypes
Frank can be BO= B blood …no worries
We can also predict the future
Fig 2.12
Mom = AB Dad = AB
Inheritance of blood types
Mom = AB Dad = AB
Gametes: A or B A or B
Inheritance of blood types
Mom = AB Dad = AB
Gametes: A or B A or B
A or B
A or B
AA
AB BB
AB
Chance of each phenotype for each offspring25% AA50% AB25% BB
Mom
Dad
Inheritance of blood types
CB14.7Testcross:
determining dominant/ recessive and zygosity
CB5.21
Sickle-cell anemia is caused by a point mutation
Sickled and normal red blood cells
Mom = HS Dad = HS
H or S
H or S
HH
HS SS
HS possible offspring75% Normal25% Sickle-cell
Mom
Dad
S=sickle-cell
H=normal
Sickle-Cell Anemia:A dominant or recessive allele?
Coincidence of malaria and sickle-cell anemia
CB 23.13
Mom = HS Dad = HS
H or S
H or S
HH
HS SS
HS
possible offspringOxygen transport:75% Normal25% Sickle-cell
Malaria resistance:75% resistant25% susceptible
Mom
Dad
Sickle-Cell Anemia:A dominant or recessive allele?
S=sickle-cell
H=normal
Variation in Peas
Phenotype
Genotype
CB 14.8
CB 14.8The inheritance of genes on different chromo-somes is independent.
Y y
r R
Gene for seed color
Gene for seed shape
Approximate position of seed color and shape genes in peas
Chrom. 1/7 Chrom. 7/7
CB 15.2The inheritance of genes on different chromosomes is independent:independent assortment
CB 15.2
meiosis I
meiosis II
CB 15.2The inheritance of genes on different chromosomes is independent:independent assortment
CB 14.8
Inheritance can be predicted by probability
CB 14.9
Probability of a 4= 1/6
Probability of two 4’s in a row=1/6x1/6=1/36
Probability of 3 or 4 = 1/6+1/6= 1/3
“and” multiply
“or” add
Huntington’s Disease
D=disease
d=normal
Neurological disease, symptoms begin around 40 years old.
Mom = dd Dad = Dd
d or d
D or d
Dd
Dd dd
ddpossible offspring50% Huntington’s50% Normal
Mom
Dad
Huntington’s Disease D=disease
d=normal
Two different people:One with Huntington’s disease = Dd HhOne without Huntington’s disease = dd Hhmate. What is the probability that their offspring will have Huntington’s disease and sickle cell anemia?(Dd hh)
Two people:One with Huntington’s disease = Dd HhOne without Huntington’s disease = dd Hhmate. What is the probability that their offspring will have
Huntington’s disease and sickle cell anemia? Dd hh
Probability of each outcome:
Probability of Dd (Ddxdd) = .5
Probability of hh (HhxHh) = .25
Two people:One with Huntington’s disease = Dd HhOne without Huntington’s disease = dd Hhmate. What is the probability that their offspring will have
Huntington’s disease and sickle cell anemia? Dd hh
Probability of each outcome:
Probability of Dd (Ddxdd) = .5Probability of hh (HhxHh) = .25Multiply both probabilities .25 X.5 = 12.5%
chance Dd hh offspring
CB 14.11Many traits are coded for by more than one gene.
Eye color: One trait controlled by multiple genes
Lectures posted online after lecture.
Textbook sections and/or pages posted a few days prior to each lecture.