The cell cycle

• What happens in the G1 phase?

  organelles replicate, size of cell increases and transcription and translation to supply the high demand of protein.
• What happens in the S phase?

  Chromosomes replicate and lots of DNA synthesis.
• What happens during the G2 phase?

  energy stores used in S phase are restored, damaged chromosomes are repaired, cell size increases.
• What is the order of the cell cycle?

  1. G1
  2. S
  3. G2
  4. M
• What two things occurs in the M phase?

  1. mitosis- chromosomes split into 2 nuclei
  2. cytokinesis- whole cell separates into two daughter cells
• What types of cells enter the G naught phase?

  fully differentiated cells, Senescent cells, and B memory cells.
• What are senescent cells?

  Cells with damaged DNA
• What are the three checkpoints?

  1. G1
  2. G2
  3. Metaphase
• What does the G1 checkpoint check for?

  DNA damage and correct size of cell.
• What does the G2 checkpoint check for?

  Damaged DNA and correct size.
• What does the metaphase checkpoint check for?

  If chromosomes are arranged correctly on the mitotic spindle