mitosis

• What is the main focus of the video?

  The video focuses on how cells divide and the role of chromosomes.
• Why do multicellular eukaryotic organisms require a continuous supply of new cells?

  They need new cells for growth, development, and repair.
• What is the process through which new cells are generated called?

  The process is known as the cell cycle.
• What are the three main stages of the cell cycle?

  The three main stages are growth, DNA replication, and mitosis (and division or cytokinesis).
• What happens during the growth stage of the cell cycle?

  The cell grows in size and increases the number of subcellular structures.
• What occurs during DNA replication in the cell cycle?

  The DNA is duplicated so that each new cell will have a full set of DNA.
• How does DNA appear when a cell is not dividing?

  The DNA is spread out in long strings.
• What happens to DNA as a cell prepares for division?

  The DNA condenses into chromosomes.
• What do chromosomes contain?

  Chromosomes contain a large number of genes.
• How many copies of each chromosome do eukaryotic cells have?

  Eukaryotic cells have two copies of each chromosome, known as a pair.
• How many pairs of chromosomes do humans have?

  Humans have 23 pairs of chromosomes.
• Why can't animals of different species reproduce fertile offspring?

  Different species have different numbers of chromosomes.
• What happens to each of the 46 chromosomes during cell division?

  Each chromosome duplicates and stays attached to its original chromosome, forming an X shape.
• What is the significance of the right and left arms of the X-shaped chromosome?

  The right arm is a duplicate of the left arm, containing the same DNA.
• What occurs when the cell is ready to divide?

  All 46 chromosomes line up along the center of the cell.
• What are spindle fibers and what do they do during cell division?

  Spindle fibers attach to each half of the chromosome and pull them to opposite sides of the cell.
• What happens to the chromosomes during the division stage of cytokinesis?

  The chromosomes are pulled apart into two separate arms.
• What is cytokinesis?

  Cytokinesis is the stage where the cell membrane and cytoplasm pull apart to form two daughter cells.
• What do the resulting daughter cells have in common?

  Each daughter cell has the same DNA and is identical to each other and to the parent cell.
• What can the resulting daughter cells contribute to after division?

  The daughter cells can contribute to growth, development, or repair.
• What are the stages of the cell cycle?

  • Growth: Cell increases in size and subcellular structures.
  • DNA Replication: DNA is duplicated.
  • Mitosis and Cytokinesis: Division of the cell into two daughter cells.
• How does the structure of chromosomes change during the cell cycle?

  • Interphase: DNA is spread out in long strings.
  • Preparation for Division: DNA condenses into X-shaped chromosomes.
  • Division: Chromosomes are pulled apart into separate arms.