Section 2: Mitosis and Cytokinesis
Eukaryotic cells reproduce by mitosis, the process of nuclear
division, and cytokinesis, the process of cytoplasm division.
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What I Know
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What I Want to Find Out
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What I Learned
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5(A) Describe the stages of the cell cycle, including deoxyribonucleic
acid (DNA) replication and mitosis, and the importance of the cell cycle
to the growth of organisms.
4(B) Investigate and explain cellular processes, including homeostasis,
energy conversions, transport of molecules, and synthesis of new molecules.
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Mitosis and Cytokinesis
Essential Questions
• What are the events of each stage of mitosis?
• What is the process of cytokinesis?
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Mitosis and Cytokinesis
Vocabulary
Review
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life cycle
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prophase
sister chromatid
centromere
spindle apparatus
metaphase
anaphase
telophase
Mitosis and Cytokinesis
Mitosis
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During mitosis cell’s replicated genetic material separates and the cell
prepares to split into two cells.
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The key activity of mitosis is the accurate separation of the cell’s replicated
DNA.
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Mitosis:
• Increases the number of cells in a multicellular organism as it grows
• Replaces damaged cells
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Mitosis and Cytokinesis
The Stages of Mitosis (Mitosis Rap)
Prophase
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Prophase is the first and longest stage of mitosis.
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Cell’s chromatin tightens/condenses into chromosomes.
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Sister chromatids are structures that contain identical copies of DNA.
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The sister chromatids are attached at the centromere.
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Mitosis and Cytokinesis
The Stages of Mitosis
Prophase
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As prophase continues, spindle fibers, centrioles, and aster fibers form a
spindle apparatus.
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The spindle apparatus attaches to each of the sister chromatids before cell
division.
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Mitosis and Cytokinesis
The Stages of Mitosis
Metaphase
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The second stage of mitosis is metaphase – the shortest phase.
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Sister chromatids are pulled along the spindle apparatus toward the center of
the cell.
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They line up in the middle of the cell.
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Mitosis and Cytokinesis
The Stages of Mitosis
Anaphase
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During anaphase, the chromatids pull apart.
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The microtubules of the spindle apparatus begin to shorten.
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The sister chromatids separate.
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The chromosomes move toward the poles of the cell.
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Mitosis and Cytokinesis
The Stages of Mitosis
Telophase
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Telophase is when the chromosomes arrive at the poles and begin to
decondense.
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Two new nuclear membranes begin to form and the nucleoli reappear.
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The spindle apparatus disassembles.
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Mitosis and Cytokinesis
Cytokinesis
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After the two daughter nuclei have formed, cells undergo cytokinesis.
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In animal cells, microfilaments constrict/pinch off to form two cells.
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In plant cells, instead of pinching in half, a new structure called the cell plate
forms between the two daughter nuclei.
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Mitosis and Cytokinesis
Visualizing the Cell Cycle
Animation
FPO
Add link to animation from page 249 (figure 6) here.
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Mitosis and Cytokinesis
Review
Essential Questions
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What are the events of each stage of mitosis?
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What is the process of cytokinesis?
Vocabulary
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prophase
sister chromatid
centromere
Copyright © McGraw-Hill Education
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spindle apparatus
metaphase
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anaphase
telophase
Mitosis and Cytokinesis