Mitosis

• Why do multicellular eukaryotic organisms need new cells?

  For growth, development, and repair
• What is the process called through which cells are generated?

  The cell cycle
• What are the three main stages of the cell cycle?

  Growth, DNA replication, and mitosis
• What happens during the growth stage of the cell cycle?

  The cell increases in size and organelles
• What occurs during DNA replication in the cell cycle?

  The DNA is duplicated for new cells
• How does DNA appear when a cell is not dividing?

  As long strings spread out
• What happens to DNA when a cell prepares for division?

  It condenses into chromosomes
• What do chromosomes contain?

  A large number of genes
• How many copies of each chromosome do eukaryotic cells have?

  Two copies, one from each parent
• How many pairs of chromosomes do humans have?

  23 pairs
• Why can't animals of different species reproduce fertile offspring?

  They have different numbers of chromosomes
• What shape do duplicated chromosomes form?

  An X shape
• What is the significance of the right and left arms of a chromosome?

  They are duplicates of each other
• What attaches to the chromosomes during cell division?

  Cell fibers
• What do cell fibers do during cell division?

  They pull chromosome arms to opposite sides
• What happens to chromosomes during division?

  They are split into two separate arms
• What is the final stage of the cell cycle called?

  Division or cytokinesis
• What happens to the cell membrane and cytoplasm during cytokinesis?

  They pull apart to form two daughter cells
• What do the resulting daughter cells contribute to?

  Growth, development, or repair
• What are the stages of the cell cycle?

  1. Growth
  2. DNA replication
  3. Mitosis and cytokinesis
• What is the structure and function of chromosomes during cell division?

  • Chromosomes condense into X shapes
  • Each chromosome has two identical arms
  • Arms are pulled apart by cell fibers
  • Resulting daughter cells are identical
• What is the significance of having two copies of each chromosome in eukaryotic cells?

  • Provides genetic diversity
  • Ensures proper distribution during cell division
  • Allows for repair of damaged genes