Cell Division (Cell Cycle )

• What is the cell cycle?

  The cell cycle is the life cycle of a cell.
• What are the main phases of the interphase in the cell cycle?

  • Growth 1 (G1)
  • Synthesis (S)
  • Growth 2 (G2)
• What percentage of the cell cycle is made up by interphase?

  About 95%
• What processes occur during interphase?

  Interphase includes growth, DNA synthesis, and preparation for mitosis.
• What is mitosis?

  Mitosis is the splitting of the nucleus.
• What is cytokinesis?

  Cytokinesis is the splitting of the cytoplasm.
• What happens during the G1 phase of interphase?

  • Preparation for cell division
  • Organelle replication (e.g., mitochondria, ribosomes)
  • Cell growth in size
  • Protein synthesis
  • Energy production through respiration
• What occurs during the synthesis (S) phase of interphase?

  DNA replication occurs during the synthesis phase.
• What is the main focus of the G2 phase of interphase?

  • Checking for DNA damage
  • Ensuring proper organelle replication
  • Confirming cell size and protein synthesis
• What is the purpose of checkpoints in the cell cycle?

  Checkpoints ensure that the cell has the correct components and no errors before proceeding.
• What is the G1 checkpoint responsible for checking?

  The G1 checkpoint checks for organelle presence, cell size, and DNA errors.
• What happens if DNA damage is detected at the G1 checkpoint?

  The cell will stop progressing to the synthesis phase to prevent further damage.
• What is the G0 phase?

  The G0 phase is a resting state where the cell does not divide.
• What are the reasons a cell might enter the G0 phase?

  • Differentiation into specialized cells
  • DNA damage detected
  • Cells becoming senescent after a limited number of divisions
• What is the significance of the metaphase checkpoint?

  The metaphase checkpoint ensures that chromosomes are properly attached to spindle fibers before separation.
• What are the phases of mitosis?

  1. Prophase
  2. Metaphase
  3. Anaphase
  4. Telophase
• What is one hallmark of cancer related to the cell cycle?

  Mutated cells can bypass checkpoints and continue to divide uncontrollably.
• What is cellular senescence?


  • A state where cells can no longer divide
  • Related to aging and age-related diseases
• Summarize the cell cycle process.

  1. Interphase (G1, S, G2)
  2. Mitosis (splitting of the nucleus)
  3. Cytokinesis (splitting of the cytoplasm)
  4. Checkpoints (G1, G2, metaphase)
  5. G0 phase if errors are detected