Phases of Mitosis - Khan Academy
Key Points
- Mitosis is a process of cell division that results in two genetically identical daughter cells.
- It is a part of the cell cycle, specifically the M phase.
- Mitosis is crucial for growth, repair, and asexual reproduction.
Phases of Mitosis:
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Prophase
- Chromosomes condense and become visible.
- The nuclear envelope breaks down.
- The mitotic spindle begins to form.
- Centrosomes move to opposite poles.
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Metaphase
- Chromosomes align at the metaphase plate.
- Spindle fibers attach to the centromeres of the chromosomes.
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Anaphase
- Sister chromatids are pulled apart to opposite poles by spindle fibers.
- This ensures each new cell will receive an identical set of chromosomes.
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Telophase
- Chromatids reach the opposite poles and begin to de-condense back into chromatin.
- Nuclear envelopes re-form around each set of chromosomes.
- The spindle fibers disassemble.
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Cytokinesis
- Occurs after mitosis, splitting the cytoplasm to form two separate daughter cells.
- In animal cells, a cleavage furrow forms to divide the cells.
- In plant cells, a cell plate forms to separate the cells.
Important Details:
- Mitosis is part of the larger cell cycle which includes Interphase (G1, S, G2 phases) and the M phase (mitosis and cytokinesis).
- Each phase of mitosis ensures proper alignment and separation of chromosomes to maintain genetic consistency.
- Errors in mitosis can lead to genetic disorders or cell death.
- Regulation of the cell cycle is essential to prevent uncontrolled cell growth, leading to cancer.
- The process is highly conserved across eukaryotic organisms, showcasing its evolutionary importance.
Applications:
- Understanding mitosis is fundamental in fields like genetics, cancer research, and biotechnology.
- Target for cancer therapies aiming to inhibit rapid cell division.
These notes provide a comprehensive summary of the phases of mitosis as discussed on Khan Academy, highlighting the process, phases, and significance of mitosis in biology.