Cell cycle The phases!

Cell cycle Map

Interphase Interphase: Parts of Interphase: most of the cells “life” (G1, S, G2 phase) Parts of Interphase: G1phase: spends most of its functional life performing their assigned tasks, metabolizing, synthesizing etc. something triggers the cell to begin a cell division event Stimuli to start a cell division: To replace dead or dying cells, To produce more cells to enlarge the organism (growth and development) Reproduction, i.e. to increase the number of unicellular organisms.

S - Phase = synthesis phase. DNA molecules are copied or replicated

Gap 2 or G2 Phase The cell is preparing for the actual division events (much protein synthesis). tubulin synthesized (protein of which microtubules are made) used to manufacture the spindle apparatus G2 completes interphase now the cell is prepared for mitosis.

Chromosome structure

On to mitosis!

MITOSIS Definition: The process by which the nucleus of a cell divides into 2 identical cells. Cell Division. Diploid  2

Prophase

PROPHASE 1st stage of mitosis DNA coils into chromosomes Nuclear membrane begins to dissolve Centrioles move to opposite ends of the cell Spindle fibers begin to appear

Metaphase

METAPHASE Chromosomes line up at the equator (middle - meta) Spindle fibers attach to the chromosomes

Anaphase

ANAPHASE Chromosomes separate into separate but identical chromatids. Each chromatid is pulled by spindle fibers to the opposite poles

Telophase

TELOPHASE Cell begins to pinch in two. Nuclear membrane begins to surround new sets of chromosomes Chromosomes begin to uncoil so protein can be made

Cytokinesis

Cytokinesis Cytoplasm divides Each cell has identical DNA Cells are completely separate now. Ready for Interphase

Plant cell division absence of centrioles Cytokinesis different simply generate a new cell wall between the developing telophase nuclei CELL PLATE The cell plate originates from the fusion of several (many) vesicles which originate from the golgi.

Plant Cell Division After nucleus has divided… 2 new IDENTICAL daughter cells A plant cell after mitosis Formation of Cell Plate Vesicles that contain cell wall material

Animal cell division

Animal vs Plant (cytokinesis)

Cell Cycle v. Cell division Interphase, prophase, metaphase, anaphase and telophase (IPMAT) = Cell cycle. Prophase, metaphase, anaphase and telophase (PMAT) = Mitosis otherwise known as cell division of body cells (non-sex cells).