Heredity Notes

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Heredity Notes
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DNA

• DNA- (Deoxyribonucleic acid)- genetic material
  that carries the information about an organism
  and is passed from parent to offspring.
• Humans contain 23 pairs of chromosomes- a total
  of 46 chromosomes (23 from mom and 23 from dad).

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Heredity

• Heredity-the passing of traits from parents to
  offspring.

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Back to Nucleus

• DNA is loose strands in the nucleus (chromatin),
  but once a cell gets ready to divide, it produces
  condensed strands (Chromosomes).
• Chromosomes must replicate before they can
  divide. Why? You dont want to lose half of
  yourself do you?

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• DNA are made up four different nitrogen bases
  pairs. Adenine (A), Thymine (T), Guanine (G),
  Cytosine (C) are the nitrogen bases.
• Adenine always pairs with Thymine and Guanine
  always pairs with Cytosine.
• With these four base pairs, there are 8,000,000
  possible outcomes between two parents and the
  arrangement of chromosomes.

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Heredity Vocabulary

• Gene- a set of information that controls a trait
  a segment of DNA on a chromosome that codes for a
  specific trait (hair color, eye color, ear
  lobes).
• Traits- characteristics that an organism can be
  pass on to its offspring through its genes.

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Heredity Vocab Continued

• Alleles- the different forms of a gene.
• Homozygous trait- having two identical alleles
  for a trait.
• Heterozygous trait- having different alleles for
  a trait.
• Genotype- genetic make up.
• Phenotype- physical appearance or visible trait.