Question 1
Unit 2 style
Which statement describes what happens during anaphase of mitosis?
- Chromosomes condense and the nuclear envelope breaks down
- Chromosomes line up on the equator of the cell
- Centromeres divide and sister chromatids move to opposite poles
- Nuclear envelopes re-form around the chromosomes
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Question 2
Unit 2 style
A student counted 200 cells in a root tip squash. 30 of the cells were in mitosis. What was the mitotic index?
- 0.15
- 0.17
- 6.7
- 0.85
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Question 3
Unit 2 style
Describe the events that take place during interphase and prophase of the cell cycle.
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Question 4
Unit 2 style
Explain why mitosis produces daughter cells that are genetically identical to the parent cell, and give two uses of mitosis in a multicellular organism.
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Question 5
Unit 3 style
A student prepared a root tip squash to observe mitosis. Describe how she should prepare the slide and explain the purpose of three of the steps.
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Question 6
Unit 3 style
Identify two hazards in the root tip squash practical and state how each risk can be reduced.
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Question 7
Unit 2 style
The table shows a student's counts of cells from one root tip squash. Calculate the mitotic index. Show your working.
| Stage | Number of cells |
|---|---|
| Prophase | 18 |
| Metaphase | 9 |
| Anaphase | 6 |
| Telophase | 7 |
| Interphase | 280 |
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Question 8
Unit 2 style
The mitotic index of region X of a root tip was 0.02 and of region Y was 0.18. Suggest what this shows and one way the student could make the results more reliable.