Question

name _________________________ date _____ concept covered: name that stage! the statements below describe the events of cell division. indicate when each event occurs by placing the name of the stage in the blank. you can choose: interphase, prophase, metaphase, anaphase or telophase. ______1. the nucleolus disappears. ______2. sister chromatids are lined up at the center of the cell. ______3. the dna of the cell is replicated. ______4. chromosomes coil and thicken and first become visible as individual structures. ______5. cytokinesis occurs. ______6. the nuclear membrane fragments. ______7. the cell doubles the number of organelles. ______8. the mitotic spindle begins to form. ______9. the nuclear membrane begins to reform. ______10. the cell is not actually dividing, but carrying out normal cell activities. ______11. the nucleolus returns. ______12. centrosomes begin to move to opposite sides of the cell. ______13. chromatids are pulled to opposite sides of the cell. give the name of the stage of mitosis for each picture below. the stages are not shown in correct order. _____ _____ _____ _______

Explanation:

1. The nucleolus dissolves early in mitosis during prophase.
2. Sister chromatids align at the cell's equator during metaphase.
3. DNA replication happens in the S phase of interphase, before mitosis.
4. Chromosomes condense and become visible in prophase.
5. Cytokinesis (cell splitting) overlaps with the end of mitosis, telophase.
6. The nuclear membrane breaks down in prophase to allow spindle access.
7. Organelles duplicate during interphase to prepare for division.
8. The mitotic spindle starts forming in prophase.
9. Nuclear membranes reform around separated chromosomes in telophase.
10. Interphase is the non-dividing phase where cells perform normal functions.
11. The nucleolus reforms in the new nuclei during telophase.
12. Centrosomes move to opposite poles to form the spindle in prophase.
13. Sister chromatids are pulled apart to opposite poles in anaphase.
14. First image: Chromatids are pulled apart to opposite poles (Anaphase).
15. Second image: Chromosomes are clustered at opposite poles, spindle breaking down (Telophase).
16. Third image: Chromosomes are condensed, nuclear membrane broken down (Prophase).
17. Fourth image: Chromosomes are aligned at the cell's equator (Metaphase).

Answer:

1. Prophase
2. Metaphase
3. Interphase
4. Prophase
5. Telophase
6. Prophase
7. Interphase
8. Prophase
9. Telophase
10. Interphase
11. Telophase
12. Prophase
13. Anaphase
14. Anaphase
15. Telophase
16. Prophase
17. Metaphase