A rescue worker has an eye test that measures the electrical impulses produced by each type of cone cell when exposed to the colour of light to which it is sensitive.
| Cone cell type tested | Electrical impulses produced in 10 seconds |
|---|---|
| red-sensitive | 16 |
| green-sensitive | 1 |
| blue-sensitive | 15 |
A response below 3 impulses in 10 seconds is not sufficient for normal colour vision.
Which type of cone cell is not functioning normally?
Explain why the worker may fail to distinguish some coloured safety labels in bright light but can still locate a grey rope in very dim light.
102 exam-style questions on Edexcel GCSE Biology 2.4 The eye, covering 2.4.1 Structure and function of the eye and 2.4.2 Eye defects and their correction. Each one has a worked solution and a mark scheme showing where the marks go.