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S3: HEREDITY E5: PEDIGREES
Objective: Infer genotypes based on phenotypes in a pedigree GRAB YOUR NOTEBOOK and the green paper from the front
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I. HUMAN GENETICS AND PEDIGREES
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I. HUMAN GENETICS AND PEDIGREES
Human genetics follows the patterns seen in sexually reproducing organisms
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I. HUMAN GENETICS AND PEDIGREES
Human genetics follows the patterns seen in sexually reproducing organisms B. Females can carry sex-linked genetic disorders.
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I. HUMAN GENETICS AND PEDIGREES
Human genetics follows the patterns seen in sexually reproducing organisms B. Females can carry sex-linked genetic disorders. Males (XY) express all of their sex-linked genes.
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I. HUMAN GENETICS AND PEDIGREES
Human genetics follows the patterns seen in sexually reproducing organisms B. Females can carry sex-linked genetic disorders. Males (XY) express all of their sex-linked genes. 2. Males tend to show sex-linked disorders more than females
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C. A Pedigree is a chart for tracing genes in a family.
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C. A Pedigree is a chart for tracing genes in a family.
Phenotypes are used to infer genotypes
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C. A Pedigree is a chart for tracing genes in a family.
Phenotypes are used to infer genotypes 2. Autosomal genes show different patterns than sex-linked genes.
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How to read a pedigree: □ = male
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How to read a pedigree: □ = male ○ = female
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Horizontal lines between a male and female: marriage
How to read a pedigree: □ = male ○ = female Horizontal lines between a male and female: marriage
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Horizontal lines between a male and female: marriage
How to read a pedigree: □ = male ○ = female Horizontal lines between a male and female: marriage Horizontal lines above males and females: siblings
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Horizontal lines between a male and female: marriage
How to read a pedigree: □ = male ○ = female Horizontal lines between a male and female: marriage Horizontal lines above males and females: siblings Vertical lines: offspring
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Horizontal lines between a male and female: marriage
How to read a pedigree: □ = male ○ = female Horizontal lines between a male and female: marriage Horizontal lines above males and females: siblings Vertical lines: offspring Colored in shapes: show the phenotype
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Horizontal lines between a male and female: marriage
How to read a pedigree: □ = male ○ = female Horizontal lines between a male and female: marriage Horizontal lines above males and females: siblings Vertical lines: offspring Colored in shapes: show the phenotype Half colored in shapes: carrier
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Example: Autosomal Pedigree
How many kids did the couple in generation I have? How many of those kids got married? How many boys/girls have the disease? How does this pedigree show this disease is autosomal? Is this a dominant or recessive disease? How do you know? Write in the genotypes for each individual.
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How do autosomal dominant traits show up different on a pedigree than autosomal recessive traits?
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Example: Sex Linked Pedigree
How many kids did the couple in generation I have? How many boys/girls have the disease? How does this pedigree show this disease is sex-linked? Write in the genotypes for each individual Is it possible for a female to have a sex linked disease? What would the parents’ genotypes have to be?
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PEDIGREE WORKSHEET GRAB A PEDIGREE WORKSHEET AND COMPLETE IT IN YOUR LAB NOTEBOOK RETURN THE SHEET BEFORE THE BELL
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