Cell Cycle and DNA Replication Review Flashcards
what happens during the G1 phase of the cell cycle?
cell growth and development occurs and it conducts cellular activities
what happens during the G2 phase of the cell cycle?
the cell prepares for division, organelles used in cell division are created
what happens during the S phase of the cell cycle?
DNA replicates (copies itself)
what happens during the M phase of the cell cycle?
Nucleus divides PROPHASE: nuclear membrane disappears METAPHASE: chromosomes line up ANAPHASE: Chromosomes seperate TELOPHASE: 2 new nuclei form
what happens during the cytokinesis?
cytoplasm and organelles divide forming 2 new cells
what occurs during prophase
nuclear envelope dissolves and the chromatin coils up into sister chromatins joined by a centromere
what occurs during metaphase
chromosomes move to the middle of the cell and line up and the spindle fibers attach to the centromeres
what occurs during anaphase
the spindle fibers pull the chromosomes to the opposite poles (ends) of the cell
what occurs during telophase
the nuclear envelope forms and creates 2 nuclei
what divides in mitosis
nucleus
what divides in cytokinesis
cytoplasm and other organelles
where are the checkpoints located in the cell cycle and why are they there
G1- main decision checkpoint(checks for cell size, DNA damage) G2 ( checks for DNA damage, DNA replication completeness) Mitosis ( spindle checkpoint) checks for chromosome attachment to spindle fibers at the metaphase plate They are there to detect and fix problems
What normally happens to a cell if any of the vheckpoints are faulty
the cell fixes the damage or the cell self destructs
what happens if a cell cant stop dividing and continues to divide uncontrollably
cancer
number of divisions in mitosis
1
