Nondisjunction
The diagrams that follow show nondisjunction during mitosis, meiosis I and meiosis II in a species that has a diploid chromosome number of 8.
Nondisjunction during Mitosis
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Prophase |
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Metaphase |
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Anaphase |
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Telophase
Notice that the cell forming on the left has an extra chromosome and the cell forming on the right has a chromosome missing. |
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G1 Interphase
During this phase, the chromosomes uncoiled and not visible. |
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G2 Interphase
During this phase, the chromosomes uncoiled and not visible. |
Nondisjunction during Meiosis I
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G2 Interphase
During this phase, the chromosomes uncoiled and not visible. |
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Prophase I |
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Metaphase I |
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Anaphase I |
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Telophase I |
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Prophase II |
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Metaphase II |
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Anaphase II |
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Telophase II |
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Haploid Daughter Cells
During this phase, the chromosomes uncoiled and not visible. |
Nondisjunction During Meiosis II
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G2 Interphase
During this phase, the chromosomes uncoiled and not visible. |
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Prophase I |
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Metaphase I |
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Anaphase I |
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Telophase I |
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Prophase II |
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Metaphase II |
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Anaphase II |
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Telophase II |
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Haploid Daughter Cells
During this phase, the chromosomes uncoiled and not visible. |