MEIOSIS

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MEIOSIS

• Section 11-4

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Types of Reproduction

• Asexual
• clones
• Sexual
• variety
• fusion of sex cells

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Meiosis

• Meiosis is
• The Formation of Sex Cells
• 2 Stages of Cell Division (Meiosis I Meiosis
  II)
• Results in Chromosome number cut in half
• Results in 4 HAPLOID cells
• Meiosis forms
• Gametes (Greek for to marry) or Sex cells
• Spermatogenesis
• Oogenesis

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Terms to KNOW

• n Refers to the SETS of chromosomes
• Haploid (n)- One set of chromosomes (half the
  normal condition)
• Sex Cells
• Humans n23
• Diploid (2n)- Two Sets of chromosomes (normal
  chromosome condition)
• All other Body Cells
• Humans 2n46

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HUMANS n 23 (There are 23 SETS of
chromosomes) Diploid 46 (2n)
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MORE Terms to know

• Homologous Chromosomes- like-pairs (from
  mom-dad) Form a tetrad
• Synapsis When Homologous chromosomes come
  together
• Crossing over- DNA from one chromosomes may be
  exchanged with corresponding DNA from the other.
  (Prophase I)
• Genetic Recombination- rearrangement of genes
  chromosomes. (Prophase I anaphase I)

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CROSSING OVER

• Crossing over is the SOURCE OF ALL GENETIC
  VARIATION!
• Occurs during PROPHASE I
• Without it, we would all look identical.
• This is why we have a combination of our mother
  and fathers traits

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SYNAPSIS
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• Meiosis Animation
• Meiosis- Cells Alive
• Mitosis VS Meiosis

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