Mitosis and Meiosis

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Mitosis and Meiosis

• Cell Division and Reproduction

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MITOSIS

• Process of one cell making two new identical
  daughter cells
• Both new cells will have the same number of
  chromosomes as the original cell
• Both new cells will have the same DNA code as the
  original cell

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Phases of Mitosis an overview

• Interphase
• Prophase
• Metaphase
• Anaphase
• Telophase
• Cytokinesis
• (Create a mnemonic for IPMATC)

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MITOSIS

• INTERPHASE Cell is preparing to divide, nucleus
  visible but no chromosomes are visible, cell
  grows and DNA is duplicated

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MITOSIS

• PROPHASE Nuclear membrane disappears, DNA
  condenses into chromosomes and becomes visible
  inside cell

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MITOSIS

• METAPHASE Spindle fibers form at opposite sides
  of chromosomes chromosomes line up in center of
  cell

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MITOSIS

• EARLY ANAPHASE Spindle fibers attach to
  chromosomes pull one chromosome set to each side
  of cell

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MITOSIS

• LATE ANAPHASE Chromosomes are at opposite sides
  of the cell spindle fibers disappear

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MITOSIS

• TELOPHASE Chromosome sets assemble at opposite
  poles and a nuclear envelope reforms around each
  set.

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Mitosis

• CYTOKINESIS Cytoplasm fully divides and two new
  cells are formed. Each new cell is ½ the size of
  the original cell.

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MITOSIS

• One large cell makes two smaller cells with same
  number of chromosomes allows organisms to grow

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MEIOSIS

• One large cell will produce 4 smaller cells
• Each cell will have ½ the normal number of
  chromosomes
• The cells produced during meiosis will fuse
  together during sexual reproduction
• May be called egg and sperm or and -

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MEIOSIS

• Looks like two versions of mitosis
• DNA does not duplicate a second time through
  prophase
• 1 cell makes two identical cells, then each of
  these makes two cells with ½ the normal number of
  chromosomes

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MEIOSIS

• The egg cell and sperm cell combine to form a
  zygote (new organism)
• ½ chromosomes in egg ½ chromosome in sperm
• NEW ORGANISM WITH RIGHT NUMBER OF CHROMOSOMES

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MEIOSIS

• One cell makes 4 reproductive cells