You will determine the parts of the cell cycle and phases of mitosis through the investigation of onion root cells.
After completing this tutorial, you will be able to complete the following:
The cell cycle is a series of processes that leads to the division and duplication of cells. Essentially, it is the life cycle of a cell. When a new cell is formed, it begins in a stage called interphase. During this time, the cell carries out normal functions and grows. This first period of interphase is known as the G1 phase/period. Next, the cell enters the S phase in which the DNA is replicated. Finally, in the G2 period, the cell continues to grow in size and prepares for cell division. Interphase is the longest phase of the cell cycle.
Following interphase, the cell enters the period of mitosis. During mitosis, the cell's nucleus (and thus, the genetic material) is completely divided in two through a series of phases, which include the prophase, metaphase, anaphase, and telophase phases. During prophase, the chromosomes condense, and the nuclear membrane disappears. Next, during metaphase, the chromosomes line up and down the middle of the cell. During the anaphase stage, sister chromatids separate and are pulled to the opposite ends of the cell. Finally, during the telophase stage, two new nuclei begin to form.
The last major phase of the cell cycle is cytokinesis. In this phase-the shortest part of the cell cycle-the materials in the cytoplasm of the newly forming cells replicate and divide. The end result is two new and genetically identical cells.
|Approximate Time||20 Minutes|
|Pre-requisite Concepts||Learners must have basic understanding of what a cell is and the structures of the cell. Learners must know what a chromosome is.|
|Type of Tutorial||Concept Development|
|Key Vocabulary||anaphase, asexual reproduction, biology|