1. SC.912.L.16.14

2. The Cell Cycle Cells must divide to maintain maximum efficiency. Mitosis is the process in which somatic (body) cells divide to form a new cell. Mitosis consists of four phases. Interphase is the period in between each mitotic cell division.

3. Interphase Interphase is made of 3 stages. The Gap 1 and 2 or G1 and G2 phase is when cells grow and make RNA, proteins, and other macromolecules. The S or Synthesis phase is when the cell is making DNA.

4. S Phase During the S phase of the cell cycle, DNA replicates. A short section of the DNA uncoils. New nucleotides bond to the open sections of the DNA. The “new” and “old” sections of DNA separate and now there are 2 DNA strands.

5. Interphase ATP is synthesized. Damaged parts are repaired. Wastes are excreted. Proteins are made. Organelles are formed. Chromosomes are copied. Specialized tasks are performed.

6. Mitosis Mitosis consists of four phases Prophase Metaphase Anaphase Telophase

7. Prophase Longest phase. Chromatin coils. Nucleus disappears. Centrioles migrate. Spindle forms.

8. Metaphase Chromatids attach to spindle fibers. Chromatids migrate to equator of spindle.

9. Anaphase Centromere splits. Chromatids are separated. Chromatids are now called chromosomes.

10. Telophase Cytoplasm divides. Nucleus reappears. Chromosomes uncoil.

11. Cytokinesis In the process called cytokinesis, the cytoplasm divides and two identical daughter cells are formed.