Tuesday, January 25, 2011

The Cell Cycle

DEFINITION
The cell cycle, also called the  cell division cycle, is the series of events that takes place in a cell leading to its division and duplication.

EVENTS OF THE CELL CYCLE
G1 Phase- Growth
S Phase- DNA Replication
G2 Phase- Mitosis Preparation
Mitosis- Cell Division
Cytokinesis- Cell Separation

Mitosis

Definiton
Mitosis is the process that eukaryotic cells separate the chromosomes in their nucleus into two identical sets in two nuclei.

The Stages Of Mitosis
Interphase- The stage of Mitosis when the cell spends most of it's time preparing for cell division. To prepare for cell division the cell grows in size and makes a copy of it's DNA.
Prophase- The stage of Mitosis when the chromosomes condense and become more visible. This is also when the nuclear membrane breaks down.
Metaphase- The stage of Mitosis when the chromosomes align in the middle of the cell before being separated into the two daughter cells.
Anaphase- The stage of Mitosis when each chromatid line up on opposite poles of the cell.
Telophase- The stage of Mitosis when nuclei form in the two daughter cells. This is also when the nuclear envelopes begin to form around the two daughter cells.
Cytokinesis-The last stage of Mitosis when the cytoplasm of the original cell is equally divided to the two daughter cells. At the end of this stage there are two separate daughter cells.