Genetics

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Genetics

• Travis Mackoy

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Gregor Mendel

• 1860s
• Developed basic principles of genetics
• Studied genetics of pea plants

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Basic Terminology

• Gene- Basic Unit of heredity
• Allele- Gene that exists in gt1 form
• Genotype- Genetic makeup of individual
• Phenotype- Physical manifestation of
  genotype

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Mendels First LawLaw of Segregation

• Genes exist in alternate forms
• Two alleles for each inherited trait one from
  each parent
• Alleles separate during meiosis, resulting in
  gametes carrying one allele
• And

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Dominance

• If two alleles are different, one will be
  dominant and the other will be silent.
• Dominant- denoted by capital letter
• Recessive- denoted by lower case letter

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Punnett Square

• Way to predict monohybrid cross
• Aa x Aa
• Ablack flowers, awhite flowers

Genotype 131 Phenotype 3 Black 1 White
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Mendels Second LawLaw of Independent Assortment

• Dihybrid Cross

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The Chromosomal Theory of Inheritance

• Crossing Over/ Genetic Recombination
• Occurs during meiosis (Prophase I)

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Variations on Mendelian Genetics

• Incomplete Dominance
• Co-dominance
• Sex Determination
• Females have XX, while males have XY