Cell cycles, Chromosomes & Mitosis

• What is the main focus of the video discussed in the study material?

  The role of chromosomes in cell division
• Why do multicellular eukaryotic organisms require a continuous supply of new cells?


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

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


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


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


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


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

  It condenses into chromosomes
• What are chromosomes described as?


  Packets of DNA
• 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?


  Due to differences in the number of chromosomes
• What happens to each chromosome during cell preparation for division?


  Each chromosome duplicates and stays attached to its original
• What shape do chromosomes take after duplication?


  An X shape
• What does each arm of the X-shaped chromosome represent?


  Identical DNA from the original chromosome
• What occurs when the cell is ready to divide?


  All chromosomes line up along the center of the cell
• What attaches to the chromosomes during cell division?


  Fibers from either side of the cell
• What happens to the chromosomes during the pulling process in cell division?


  The chromosomes are pulled to opposite sides of the cell
• What is the final stage of the cell cycle called?

  Cytokinesis
• What occurs during cytokinesis?


  The cell membrane and cytoplasm pull apart to form two daughter cells
• What is true about the resulting daughter cells after division?


  They have the same DNA and are identical to each other and the parent cell
• What can the resulting daughter cells do after division?


  Contribute to growth, development, or repair
• What are the stages of the cell cycle?


  1. Growth
  2. DNA replication
  3. Mitosis (cytokinesis)
• How does the structure of chromosomes change during the cell cycle?


  • DNA is spread out as long strings when not dividing
  • DNA condenses into X-shaped chromosomes during preparation for division
  • Each chromosome duplicates and forms two identical arms
• What is the significance of chromosomes in eukaryotic cells?


  • Carry genetic information
  • Control development of characteristics
  • Ensure proper distribution of DNA during cell division