Ronald Mathis
Grand Canyon University
Biology 100
July 10th 2011

The Cell Cycle

Directions: Answer the following questions. Cite references as needed. Be sure to read the required Module 3 readings and view the required Web sites before completing the assignment.

Cell Cycle

Questions for Cell Cycle
1) . Briefly describe all phases of the cell cycle and tell what happens in each.
a) Interphase: G1 phase, S phase, G2 phase Interphase: Before a cell can enter cell division, it needs to take in nutrients. All of the preparations are done during the interphase. Interphase proceeds in three stages, G1 phase, S phase, G2 phase. Cell division operates in a cycle. Therefore, interphase is preceded by previous cycle mitosis and cytokinesis (Module 3 Readings). a. G1 phase: The cell increases the supply of proteins and increases its organelles. b. S phase: Linear chromosome is replicated. c. G2 phase: Increases protein preparing to replicate. (Module 3 Readings)

b) M phase: M phase is a method of indirect cell division by means of which the two daughter nuclei normally receive identical complements of the number of chromosomes of the somatic cells of the species.

2) Which phase is the shortest?

Anaphase is the shortest phase of mitosis because its where the chromatids twins are all pulled apart at the centromere by the spindle fibers.

3) What is G0 (Gap 0/Resting phase)? A resting phase is when or where the cell has left the cycle and has stopped dividing.

4) If a cell never entered the resting phase would it be a problem? Why? It would continually reproduce, bypassing all the reproduction checkpoints, which would greatly increase the chance of it becoming cancerous or making defects and mutations in its offspring.

5) Certain cells in the body stay in Gap 0 and rarely, if ever, divide. Name 2 cell types in the