cell cycle

• What are the two main stages of cell division?

  Nuclear division and cell division
• What is nuclear division?

  It is the process where the nucleus divides.
• What are the two types of nuclear division?

  Mitosis and meiosis
• Why must DNA be replicated before nuclear division?

  To ensure daughter cells have the genetic information needed.
• What are the four requirements for semi-conservative replication?

  • Four types of nucleotide must be present.
  • Both strands of DNA must act as templates.
  • DNA polymerase is needed to catalyze the reaction.
  • A source of chemical energy is required.

  
• What is the role of DNA helicase in semi-conservative replication?

  It breaks the hydrogen bonds linking the base pairs.

  
• What happens during the second step of semi-conservative replication?


  The double helix separates into its two strands and unwinds.
• What is the function of DNA polymerase in semi-conservative replication?

  It joins the nucleotides to form the missing polynucleotide strand.
• How many daughter nuclei does mitosis produce?

  Two daughter nuclei
• How does meiosis differ from mitosis in terms of daughter nuclei produced?

  Meiosis produces four daughter nuclei, each with half the chromosomes.
• What is the significance of mitosis in cell division?

  It results in daughter cells having an exact copy of the parent's DNA.
• What is interphase?


  It is the period when the cell is not dividing.

  
• What are the stages of mitosis?

  1. Prophase: Chromosomes become visible, nuclear envelope disappears.
  2. Metaphase: Chromosomes arrange at the center of the cell.
  3. Anaphase: Chromosome threads migrate to opposite poles.
  4. Telophase: Nuclear envelope reforms.
• Why is mitosis important for growth?

  It produces daughter cells that are identical to the parent cells.
• How does differentiation relate to mitosis?


  Cells change to form specialized cells that divide by mitosis.
• What role does mitosis play in repair?

  It ensures new cells have identical structure and function to those lost.
• What are the three stages of the cell cycle?

  1. Interphase: Resting phase with no division.
  2. Nuclear division: Nucleus divides into two or four.
  3. Cell division: Whole cell divides into two or four.
• How long does a mammalian cell take to complete a cell cycle?

  About 24 hours
• What causes cancer?

  Damage to the genes that regulate mitosis and the cell cycle.
• What is the result of uncontrolled cell growth in cancer?

  A tumor develops and expands in size.
• How do cancer treatments disrupt the cell cycle?

  • Preventing DNA from replicating.
  • Inhibiting the metaphase stage by interfering with spindle formation.
• What is a consequence of cancer treatment drugs on normal cells?


  They also disrupt the cell cycle of normal cells.