Download Chapter 5 – Extensions and Exceptions to Mendel`s Law

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Chapter 5 – Extensions and Exceptions to Mendel’s Law
STANDARDS – 3c -----ESLRS-EFFECTIVE
EFFECTIVE PROBLEM SOLVERS, CITIZENS AND COMMUNICATORS
Read and Outline
chapter
4.1 and ch 5
Write objectives in this
column.
Applied questions ch 4
p.93 # 8-18
Review questions ch 5 p.
109 #1
Applied question p. 109
#1
Study guide
Check with power point
Warm up
What is cystic fibrosis and what are some of the treatments?
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Pedigree symbols
Copy
Human Inheritance
Patterns
Notes - List autosomal
recessive disorders from
the power point and
then autosomal
dominant disorders
Recessive
Cystic Fibrosis
Sickle cell anemia
Phenylketonuria
Xeroderma Pigmentosum
Tay-Sachs
Dominant
Marfan Syndrome
Neurofibromatosis
Huntington’s Disease
Achondroplasia
Familial hypercholesterolemia
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Constructing Pedigrees
Complete worksheet
And copy down the
expectations of a
autosomal recessive
pedigree
Case Study – Cleft Lip
Inheritance
Question- List 3 ways
your baby can have a
cleft lip.
More Autosomal
Recessive Pedigrees
Complete worksheet
Warm up
Mitochondrial genes p.
101-103
Mitochondrial Genes –
Fact sheet
Case Study – Kern Sayre
syndrome and
Mitochondrial disorders
Question – Why would
mitochondria have their
own genomes?
How would
mitochondria be passed
See power point for answers
See power point for answers
What is a pedigree? What do circles, squares, lines etc. represent?
Mitochondrial Genes – Fact sheet
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from mother to offspring
during egg formation?
Why doesn’t the father
pass on mitochondria to
offspring?
Case study – Pearson
Syndrome
Question- How would a
large deletion in the
mitochondrial genome
cause a disease?
Warm up
Quiz – autosomal
recessive pedigree
Psychosocial Issues: Your
child has Cystic Fibrsis
Answer question for
each situation.
What are mitochondrial genes and how are they different that our
other genes?
Situation 1 –
Situation 2 –
Situation 3 –
Situation 4 –
Situation 5 –
Situation 6 –
Situation 7 –
Situation 8 –
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Situation 9 –
Situation 10 –
Situation 11Case Study – CF and
Genetic Testing
Question- If this child has
CF, what are the
chances that any future
child will have this
disease? Does that fact
they have a healthy 5year old son affect the
chances of having
future children with CF?
Biotech/Pharmaceutical
Company Team Project
Read handouts
Define and give
examples of Epistasis,
pleiotropic, phenocopy,
and genetic
Heterogeneity
Epistasis –
Pleiotropic –
Phenocopy –
Genetic heterogeneity
Warm up
Explain Pleiotropic vs heterogeneity
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Autosomal Dominant
Inheritance notes
Variable expressivity
Penetrance
Lack of penetrance (incomplete penetrance)
Percent penetrance
Fresh (spontaneous) mutations
Delayed onset
Pleiotropy
Case study – Hardy
Weingberg and CF
Question – If you were
their genetic counselor,
would you recommendd
that Jane and John be
genetically tested
before they attempt to
have any children?
Case study – Cystic
Fibrosis gene
Question – Why do you
think a change in one
amino acid in the CF
gene can cause such
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severe effects in CF
patients? Relate you
answer to the CFTR
protein function and the
cell membrane.
Warm up
List the differences between autosomal recessive and autosomal
dominant inheritance.
Warm up
Explain Variable expressivity, Lack of penetrance,
Fresh mutations, Delayed onset
Autosomal Dominant
Pedigree
Complete worksheet
Warm up
Check with power point
Dominant Hereditary
Ataxia
Complete worksheet
Case Study –
Achondroplasia
Question – What is the
Check with power point
What is ectodactyly? How do you get it?
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chance this couple will
have a child with two
copies of the dominant
mutant gene? What is
the chance the child will
have normal height?
Should the parents be
concerned about the
heterozygous condition
as well as the
homozygous mutant
condition?
Warm up
Quiz – Autosomal
Dominant pedigree achondroplasia
Review power point 1-20
Study for ch 4-5 test
Biotech/pharmaceutical
group project
Review for final exam
Would you get a gene test for Huntington’s. Why or why not?
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Chapter 5 - Extensions and Exceptions to Mendel's Laws - Study Guide
*Some combinations of alleles cause problems so severe that the fetus ceases to develop. Why do such lethal allele combinations
appear to alter Mendelian ratios?
*What is the presence of two different alleles in mitochondria within the same cell called?
*If allele T (long tongue) exhibits incomplete dominance over the recessive allele t (short tongue), a heterozygote for this tongue gene
would most likely have what kind of tongue?
*Different alleles that are both expressed in a heterozygote are what?
*Can a woman with blood type A have a child with blood type O with a man who is AB?
*Some people with polydactyly have more than 5 fingers, while others do not. This is an example of a phenotype that is called what?
*A family has an autosomal dominant condition where the second toe is attached by webbing to the third toe and is longer than the
big toe. Only some family members who inherit the mutant gene have the odd toe, and the extent of webbing varies. Is this
phenotype codominant, pleiotropic, incompletely expressed, variably expressed, or phenocopy?
*A Mendelian disorder that has many associated symptoms called what?
*A trait caused by an environmental influence that appears to be inherited is called what?
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*In a heterozygote for two linked genes, when both dominant alleles are on one chromosome and both recessive alleles are on the
other, the genes are in what?
*How does a geneticists construct linkage maps of chromosomes?
*A and B are linked genes. In a study of 100 offspring, 94 had parental genotypes for A and B, while 6 were recombinants. A and B are
how many map units apart?
*A, B, and C are linked genes. Recombination between A and B is 3%; between A and C is 6%; and between B and C is 9%. What is the
order of these genes on the chromosome?
*The alleles that control which blood group antigens appear on the surfaces of red blood cells show what type of inheritance?
*Is Marfan syndrome an example of a Mendelian trait that is pleiotropic?
*The drug thalidomide causes birth defects that resemble those that occur in the inherited disease phocomelia. The defects
thalidomide causes are a called what?
*Genetic disorders such as deafness, cleft palate, and albinism that may be caused by different genes that produce similar
phenotypes are examples of what?
*A man with a recessive deafness allele on chromosome 17 marries a woman who also has a recessive deafness allele, but on
chromosome 3. Based on this, the probability that their children will be deaf is closest to what?
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*How does Mitochondrial DNA differs from nuclear DNA?
*The mode of transmission of a mitochondrial trait is unusual in that it passes from who to who?
*Of nearly 200 forms of hereditary deafness, 132 are autosomal recessive, 64 autosomal dominant, and 4 X-linked recessive. Hereditary
deafness is genetically what?
*Enamel hypoplasia is an autosomal dominant disorder that results in holes and cracks around the crowns of baby teeth. Some
individuals are apparently unaffected but transmit the trait to their offspring. Individuals with the trait also vary in the number of
teeth affected. This trait is an example of what?
* Are early acting lethal alleles responsible for spontaneous abortion in humans?
*What is the probability that a pregnancy will spontaneously abort if the mother and father both carry a recessive lethal allele for the
same gene?
*Hairless trait in dogs is a dominant allele. Inheriting one dominant allele results in a hairless dog. Inheriting two dominant alleles is lethal
to the embryo. In a cross between two hairless dogs, what is the probability that a puppy will be born with a dominant allele?
*Hairless trait (H) in dogs is dominant to hairy (h) and lethal when homozygous. In a cross between a hairless and a hairy dog, what is
the chance that an embryo will receive a dominant allele?
*Hairless trait (H) in dogs is dominant to hairy (h) and lethal when homozygous. Hairless, hairy and lethal represent what?
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*Hairlessness in dogs is a dominant trait. Inheriting one dominant allele results in a hairless dog. Inheriting two dominant alleles is lethal
for the embryo. In a cross between two hairless dogs, what is the probability that a hairy puppy will be born?
*Hairless trait (H) in dogs is dominant to hairy (h) and lethal when homozygous. How would you create a pure breeding line of hairless
dogs?
*A cross of pure breeding red snapdragons with pure breeding white snapdragons always produces plants with pink flowers. Is this an
example of incomplete dominance?
*A cross of pure breeding red snapdragons with pure breeding white snapdragons always produces plants with pink flowers. How
would you produce a pure breeding line of pink snapdragons?