Cells cycle - chromosomes and 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?

  • Growth
  • DNA replication
  • Mitosis and division (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 has a full set of DNA.
• How does DNA appear when a cell is not dividing?

  DNA is spread out in long strings.
• What happens to DNA when 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 do fibers do during the cell division process?

  Fibers attach to each half of the chromosome and pull them to opposite sides of the cell.
• What is the final stage of the cell cycle called?

  The final stage is called cytokinesis.
• What happens during cytokinesis?

  The cell membrane and cytoplasm pull apart, forming two daughter cells.
• What do the resulting daughter cells contribute to after division?

  The daughter cells contribute to growth, development, or repair.
• What is the overall purpose of the cell cycle?

  • To generate new cells for growth
  • To replace lost or damaged cells
  • To ensure proper DNA replication and distribution