Cell Cycle By: Selena Siegal Biology Period 2 30 September 2004
Over View • G1 Phase • S Phase • G2 Phase • PMAT • Mitosis • Cytokinesis • The difference between meiosis and mitosis. • Conclusion
G1 Phase G1 can also be called Interphase. G1 is the longest phase of them all. The parent cell forms daughter cells in the cytokinesis The daughter can begin to grow once the energy is restored.
S Phase S means Synthesis and Synthesis means to make. In a process called replication each cell’s DNA is copied. The Definition of replication is: The processing of copying a DNA molecule
G2 Phase A lot of time and energy is expected to make DNA replication take place. The gap is created by the time that it takes to gain the energy back.
PMAT • The chromatin coils up and forms chromosomes, and the nuclear membrane disappears and the centrioles go to either side of the cell. • Then the spindle fibers form. • Polar fibers go from centriole to centriole • Kinetochore fibers go from the middle of the chromosomes to the centrioles. • Protein fibers go from each centriole to another.
Mitosis • The process in which DNA is divided into 2 identical sets • This takes place before the cell divides.
Cytokinesis Cytokinesis is the division of the cytoplasm of a parent cell. The cell comes very close together in the middle.
Mitosis No DNA is replicated Chromosomes separate and daughter cells divide. You end up with 4 daughter cells at the end each has DNA from the parent. Meiosis The DNA is replicated. The parent cell makes 2 daughter cells with an original pair of chromosomes The difference between mitosis & meiosis
Conclusion • Mitosis is the process in which the 2 daughter cells divide into 4 and each get ½ the chromosomes from the parent. • Meiosis is the process where DNA replicates and produces 2 daughter cells with an original set of the chromosomes.