Scientists investigated growth in a plant root. They measured the length of the cells and the percentage of cells undergoing mitosis at different distances from the tip of the root.
The Table shows the results.
Table
| Distance from root tip in mm\text{mm}mm | Mean length of cells in μm\mu\text{m}μm | Percentage of cells undergoing mitosis |
|---|---|---|
| 0.5 | 10 | 12 |
| 1.0 | 12 | 10 |
| 2.0 | 40 | 2 |
| 3.0 | 90 | 0 |
| 4.0 | 100 | 0 |
| 5.0 | 100 | 0 |
Describe the relationship between the distance from the root tip and the percentage of cells undergoing mitosis.
Calculate how many times longer the cells are at 5.0 mm from the root tip than at 0.5 mm from the root tip.
Explain the change in the mean length of cells between 1.0 mm and 4.0 mm from the root tip.
Use the Table to explain why the cells at 5.0 mm from the root tip are likely to be differentiated cells.
42 exam-style questions on Edexcel GCSE Biology 2.1 Cell division and growth, covering 2.1.1 Mitosis and the cell cycle, 2.1.2 Division producing identical daughter cells, 2.1.3 Cancer and uncontrolled cell division, 2.1.4 Growth in animals and plants, 2.1.5 Importance of cell differentiation, and 2.1.6 Percentile charts to monitor growth. Each one has a worked solution and a mark scheme showing where the marks go.