Onion Root Tip Lab

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Onion Root Tip Lab

• Rachel Hildreth
• Shanna Rentz

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Parts of the Onion Root

• Region of Maturation- where root hairs develop
  and cells differentiate
• -------------------------------------gt
• Region of Elongation- area in which growth occurs
• -------------------------------------gt
• Apical Meristem- region containing the highest
  percentage of cells undergoing mitosis
• ------------------------------------gt
• Root Cap- functions in protection
• --------------------------------------gt

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4 Phases of Mitosis

• Prophase
• Metaphase
• Anaphase
• Telophase/Cytokinesis (sometimes referred to 5th)

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Interphase (Pre-Mitosis)

• Cell prepares for division by
• replicating DNA and organelles
• increasing cell size

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Prophase

• Cell prepares for nuclear division by
• condensing DNA into movable packages called
  chromosomes

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Metaphase

• Cell prepares chromosomes for division by
• aligning chromosomes at cell equator
• attaching spindle fibers from each new daughter
  cell pole to each chromosome at the centromere

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Anaphase

• Chromosomes divide
• spindle fibers pull chromosomes apart
• one-half of each chromosome (chromatid) moves to
  a new daughter cell

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Telophase/Cytokinesis

• Cytoplasm divides
• DNA decondenses and two nuclei form
• new cell wall (cell plate) appears between the
  two nuclei to form two new daughter cells

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Onion Root Tip Mitosis
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