Presentation on theme: "1 1 Mitosis and the Cell Cycle Big Idea: Mitosis is the process in which the nucleus divides to form two new nuclei and two cells with identical DNA."— Presentation transcript:
1 1 Mitosis and the Cell Cycle Big Idea: Mitosis is the process in which the nucleus divides to form two new nuclei and two cells with identical DNA.
How do little elephants grow up to be BIG elephants?
The cell cycle is a repeated pattern of growth, division, and replacement that occurs in eukaryotic cells
The cell cycle is a regular pattern of growth, DNA replication, and cell division.
The main stages of the cell cycle are gap 1, synthesis, gap 2, and mitosis. –Gap 1 (G 1 ): cell growth and normal functions Mitosis occurs only if the cell is large enough and the DNA undamaged. –DNA synthesis (S): copies DNA –Gap 2 (G 2 ): additional growth –Mitosis (M): includes division of the cell nucleus (mitosis) and division of the cell cytoplasm (cytokinesis)
Chromosomes are copied (# doubles) Chromosomes appear as threadlike coils ( chromatin ) at the start, but each chromosome and its copy( sister chromosome) change to sister chromatids at end of this phase CELL MEMBRANE Nucleus Cytoplasm
Animal Cell Plant Cell Photographs from:
Mitosis begins (cell begins to divide) Centrioles (or poles) appear and begin to move to opposite end of the cell. Spindle fibers form between the poles. Centrioles Sister chromatids Spindle fibers