GHSGT Biology Review

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GHSGT Biology Review

• March 12, 2009

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The Cell Cycle
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• Interphase
• G1 cell lives and grows
• S - DNA is synthesized or replicated
• G2 - Organelles and molecules needed for cell
  division are made (shortest of 3)
• M Phase
• Mitosis (PMAT)
• Cytokinesis

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Interphase
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Mitosis

• 4 Stages PMAT (prophase, metaphase, anaphase,
  telophase)
• Occurs in all cells (Meiosis ONLY occurs in the
  sex cells more on this later)
• Chromosome Number stays the same
• Occurs in plants and animals
• Plants rectangular in shape
• Animals rounder in shape

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Prophase
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Prophase

• Drawing

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Metaphase
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Metaphase (think MIDDLE)

• Drawing

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Anaphase
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Anaphase (think APART)

• Drawing

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Telophase
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Telophase (think 2)

• Drawing

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Cytokinesis

• Division of the cytoplasm
• Actually occurs while telophase is happening
• Cell plate plant cells
• Cleavage furrow animal cells

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Cancer

• What is cancer?
• Disorder in which some of the bodys own cells
  lose the ability to control their growth.
• Disease of the cell cycle
• Body cells will divide out of control and form
  masses of cells called tumors.
• Malignant tumors are called cancerous tumors
• Cancer cells can break loose and spread
  throughout the body

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Cancer

• Causes of Cancer
• Environmental agents called carcinogens
• Oncogenes cancer genes

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Cancer

• Treatments
• Chemotherapy poisons cancer cells
• Radiation destroys chromosomes
• Surgery to remove the tumor
• New treatment include gene therapy
• Introduction of genetic material into a persons
  cells to help fight or prevent disease.

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Mitosis vs. Meiosis
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Meiosis

• Specific Differences
• Phases
• Interphase (not a part of meiosis)
• Prophase 1 Crossing-over occurs the pairing of
  homologous chromosomes forms tetrads
• Metaphase 1
• Anaphase 1 centromere does not divide
• Telophase 1 and Cytokinesis

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Meiosis

• Specific Differences cont
• INTERKINESIS not a part of meiosis
• Prophase 2
• Metaphase 2
• Anaphase 2
• Telophase 2 and Cytokinesis

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