Cell Cycle How our cells divide

2 main stages of the Cell Cycle INTERPHASE = cell growth M Phase – cell division

Interphase Most of their life of a cell is spent in this phase Carries on DAILY ACTIVITY and allows the cell to grow 3 different phases G1- ‘growth’ increasing mass of cell Number of organelles and amount of cytoplasm S phase – DNA synthesis or “Replication” G2 Phase – continues to increase in size and prepares to divide

Replication Before a cell can divide, it must duplicate (or copy) its DNA End goal = 2 identical strands of DNA One set of DNA will go to each new daughter cell Possible because of Double Helix Allows DNA to be easily copied

Mitosis a process by which cell ensures each daughter cell will have a complete set of chromosomes of DNA There are Four Key Stages of mitosis: PMAT

Prophase Vocabulary Description Centrioles = microtubules that form fibers – always in pairs Chromosomes = “X” shaped DNA – tightly coiled Centromere = the ‘glue’ that holds chromosomes together Description Chromatin condenses to form chromosomes Nuclear Envelope disappears Centrioles move to opposite poles (ends) of the cell

Prophase Diagram

Metaphase Vocabulary Description Sister chromatids = ½ of a chromosome Spindle Fibers = appear out of centrioles, like rope Description Spindle Fibers = pull chromatids to middle of cell Sister chromatids = attach to spindle fibers and move to center of cell Shortest phase = ensures accurate DNA copies are made

Metaphase Diagram

Anaphase Vocabulary Description Microtubules = centrioles Spindle fibers = pull sister chromatids apart from each other Sister chromatids = separated and go to opposite ends of cell Microtubules = shorten allowing this process to occur

Anaphase Diagram

Telophase Description Chromosomes begin to unravel into chromatin New nuclear envelope forms around each complete set of DNA

Telophase Diagram

Cytokenesis Vocabulary Description Daughter cell = identical copy of parent Cleavage furrow = pinching that separates parent cell Cell plate = CF in plants Description Cytoplasm and organelles are divided into 2 identical daughter cells Plant cells = cell plate Animal cells = cleavage furrow

Cyto Diagram