2 The Cell CycleMost cells in an organism go through a cycle of growth, development, and division called the cell cycle.The cell cycle allows organisms :to grow and developreplace old or damaged cellsproduce new cells.
3 Phases Of The Cell Cycle There are two main phases of the cell cycle:InterphaseMitotic phase
4 InterphaseInterphase is a period of growth and development for a cell.It makes up most of the cell cycleDuring interphase, The DNA of the cell is called chromatin
5 Interphase During interphase, cells go through three stages: 1. Rapid growth and replication of the organelles. (G1 stage)
6 Interphase 2. Replication of DNA . (S stage) The cell replicates its strands of chromatinSister chromatids are the two identical strands of DNA that make up the duplicated chromosome.They are held together by a structure called a centromere.
7 Interphase3. Growth and final preparation for cell division (G2 Stage
8 Mitotic PhaseMitosis- The process of cell division that results in 2 identical cells(daughter cells) with the same number of chromosomes.Only happens in body cellsSub-stages of Mitosis:ProphaseMetaphaseAnaphaseTelophaseCytokinesis
9 ProphaseDuplicated DNA condenses into chromosomes
10 MetaphaseChromosomes line up in the middle of the cell
11 AnaphaseSister chromatids in each duplicated chromosome separate and are pulled in opposite directions by the spindle fibers
12 TelophaseChromosomes begin to uncoil, and 2 new identical nuclei form
13 CytokinesisCytokinesis divides a cell’s cytoplasm forming a new cell membrane around each daughter cell.In animal cells , a furrow in the middle of the cell gets deeper until the cell membrane comes together to divide the cell.
14 CytokinesisIn plants, a cell plate grows outward toward a new cell wall until 2 new cells form
15 The cell cycle is important for : for reproduction in some organismsgrowth in multi-cellular organismsreplacement of worn-out or damaged cellsRepair of damaged tissues