Download 5.1 The Cell Cycle

5.1 The Cell Cycle
KEY CONCEPT
A cell’s life consists of a repeating pattern of
events called the cell cycle.
5.1 The Cell Cycle
Cell Cycle Events include:
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Growth
Carrying out is job
DNA and organelle duplication
Division
5.1 The Cell Cycle
The Cell Cycle is divided into two main stages:
Interphase and Cell Division
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5.1 The Cell Cycle
INTERPHASE
Purpose: Grow, Carry out Job, Prepare for Cell Division
G1 - Cell growth, Do job
Duplicate organelles
S - DNA synthesis (copies DNA)
G2 - Additional growth,
Duplicate organelles
Normal functions
5.1 The Cell Cycle
2 Parts of Cell Division “M” Stage:
1. Mitosis
2. Cytokinesis
5.1 The Cell Cycle
MITOSIS
“Nuclear Divison”
Purpose:
Divides nucleus into 2 genetically identical nuclei
4 Stages of Mitosis:
• Prophase
• Metaphase
• Anaphase
• Telophase
5.1 The Cell Cycle
CYTOKINESIS
PURPOSE:
Divide the cytoplasm to form two separate cells
Animal Cell
Plant Cell
5.1 The Cell Cycle
The Final Product of the Cell Cycle……
• 2 Daughter Cells that are genetically identical to the parent
cell – same # of chromosomes with same DNA information
Start of Interphase
End of Interphase/
Beginning of Mitosis
End of Mitosis
End of Cytokinesis
5.1 The Cell Cycle
Reasons Cells Divide
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Growth
Replacement
Repair
Maintain size limit (surface area to volume ratio)
5.1 The Cell Cycle
Cell size is limited.
• Volume increases faster than surface area.
5.1 The Cell Cycle
Cells divide at different rates.
• The rate of cell division varies with the need for those
types of cells.
• Some cells are unlikely to divide (G0) Ex. Neurons (nerves).