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31 Cards in this Set
- Front
- Back
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G2 of Interphase |
A nuclear envelope encloses the nucleus. |
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G2 of Interphase |
The nucleus contains one more more nucleoli (singular, nucleolus). |
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G2 of Interphase |
Two centrosomes have formed by duplication of a single centrosome. Centrosomes are regions in animals cells that organize the microtubules of the spindle. Each centrosome contains two centrioles. |
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G2 of Interphase |
Chromosomes, duplicated during S phase, cannot be seen individually because they have not yet condensed. |
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Prophase |
The chromatin fibers become more tightly coiled, condensing into discrete chromosomes observable with a light microscope. |
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Prophase |
The nucleoli disappear. |
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Prophase |
Each duplicated chromosome appears as two identical sister chromatids joined at their centromeres and, in some species, all along their arms by cohesins (sister chromatid cohesion). |
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Prophase |
The mitotic spindle (named for its shape) begins to form. It is composed of the centrosomes and the microtubules that extend from them. The radial arrays of shorter microtubules that extend from the centrosomes are called asters. |
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Prophase |
The centrosomes move away from each other, propelled partly by the lengthening microtubules between them. |
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Prometaphase |
The nuclear envelope fragments. |
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Prometaphase |
The microtubules extending from each centrosome can now invade the nuclear area. |
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Prometaphase |
The chromosomes have become even more condensed. |
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Prometaphase |
Each of the two chromatids of each chromosome now has a kinetochore, a specialized protein structure at the centromere. |
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Prometaphase |
Some of the microtubules attach to the kinetochores, becoming "kinetochore microtubules," which jerk the chromosomes back and forth. |
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Prometaphase |
Nonkinectochore microtubules interact with those from the opposite pole of the spindle. |
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Metaphase |
The centrosomes are now at opposite poles of the cell. |
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Metaphase |
The chromosomes have all arrived at the metaphase plate, a plane that is equidistant between the spindle's two poles. The chromosomes' centromeres lie at the metaphase plate. |
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Metaphase |
For each chromosome, the kinetochores of the sister chromatids are attached to kinetochore microtubules coming from opposite poles. |
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Anaphase |
The shortest phase of mitosis, often lasting only a few minutes. |
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Anaphase |
Begins when the cohesin proteins are cleaved. This allows the two sister chromatids of each pair to part suddenly. Each chromatid thus becomes a full-fledged chromosome. |
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Anaphase |
The two liberated daughter chromosomes begin moving toward opposite ends of the cell as their kinetochore microtubules shorten. Because these microtubules are attached at the centromere region, the chromosomes move centromere first. |
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Anaphase |
The cell elongates as the nonkinetochore microtubules lengthen. |
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Anaphase |
By the end of this stage, the two ends of the cell have equivalent --and complete -- collections of chromosomes. |
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Telophase |
Two daughter nuclei form in the cell. |
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Telophase |
Nuclear envelopes arise from the fragments of the parent cell's nuclear envelope and other portions of the endomembrane system. |
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Telophase |
Nucleoli reappear. |
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Telophase |
The chromosomes become less condensed. |
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Telophase |
Any remaining spindle microtubules are depolymerized. |
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Telophase |
Mitosis, the division of one nucleus into two genetically identical nuclei, is now complete. |
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Cytokinesis |
The division of the cytoplasm is usually well underway bylate telophase, so the two daughter cells appar shortlyafter the end of mitosis. |
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Cytokinesis |
Involves the formation of a cleavage furrow. which pinches the cell in two. |
