Genetics

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Genetics
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Genetics

• The branch of biology that studies heredity

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Genetics Before Mendel (Misconceptions)

• Heredity was not seriously studied until second
  half of nineteenth century.

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Hippocrates

• First scientist to ponder heredity was
  Hippocrates (460-377 BC)
• Hypothesized specific particles or seeds were
  produced by all parts of the body

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Aristotle

• Aristotle rejects Hippocrates ideas one century
  later
• Believed male semen was made up of imperfectly
  blended ingredients which included past
  generations
• When mixed with female semen or menstrual
  fluid, it was given the power to form flesh and
  blood to develop the offspring

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More Misconceptions

• Aristotles beliefs were accepted for the next
  2,000 years.
• Society also begins to believe in spontaneous
  generation during this time

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Recipe for Mice

• Put one dirty shirt into a pot
• Add handful of wheat grains into pot
• Set in corner of barn for 21 days

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Leeuwenhoek

• 1677 Leeuwenhoek discovers sperm
• Believed that each sperm contained a homunculus
  or little man

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De Graaf

• 1670s de Graaf discovers female egg
• Believed the homunculus was in each egg

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Even More Misconceptions

• Middle of nineteenth century scientists and
  society believed in blending

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Gregor Mendel to the Rescue