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The Cell Cycle & Cell Division. Most 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 develop replace old or damaged cells produce new cells. The Cell Cycle.
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Most 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 develop • replace old or damaged cells • produce new cells. The Cell Cycle
There are two main phases of the cell cycle: • Interphase • Mitotic phase Phases Of The Cell Cycle
Interphase is a period of growth and development for a cell. • It makes up most of the cell cycle • During interphase, The DNA of the cell is called chromatin Interphase
During interphase, cells go through three stages: 1. Rapid growth and replication of the organelles. (G1 stage) Interphase
2. Replication of DNA . (S stage) • The cell replicates its strands of chromatin • Sister chromatids are the two identical strands of DNA that make up the duplicated chromosome. • They are held together by a structure called a centromere. Interphase
3. Growth and final preparation for cell division (G2 Stage Interphase
Mitosis- The process of cell division that results in 2 identical cells(daughter cells) with the same number of chromosomes. • Only happens in body cells • Sub-stages of Mitosis: • Prophase • Metaphase • Anaphase • Telophase • Cytokinesis Mitotic Phase
Sister chromatids in each duplicated chromosome separate and are pulled in opposite directions by the spindle fibers Anaphase
Chromosomes begin to uncoil, and 2 new identical nuclei form Telophase
Cytokinesis 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. Cytokinesis
In plants, a cell plate grows outward toward a new cell wall until 2 new cells form Cytokinesis
The cell cycle is important for : • for reproduction in some organisms • growth in multi-cellular organisms • replacement of worn-out or damaged cells • Repair of damaged tissues