A student uses three different light microscopes to examine an unknown organism from a pond. The organism grows as a chain of cells joined end to end, and the cells are all about the same length.
The table shows the student's measurements.
| Microscope | Diameter of field of view in mm | Number of cells that fit end to end across the diameter |
|---|---|---|
| A | 0.42 | 7 |
| B | 0.48 | 8 |
| C | 0.55 | 10 |
Calculate the mean estimated length of one cell in micrometres.
Show your working.
Suggest whether the cells are more likely to be prokaryotic or eukaryotic.
Explain your answer.
130 exam-style questions on OCR GCSE Biology 1.1 Cell structures, covering 1.1.1 Viewing cells with light microscopes, 1.1.2 Sub-cellular structures and functions, and 1.1.3 Electron microscopy and resolution. Each one has a worked solution and a mark scheme showing where the marks go.