A researcher records electrical activity at three positions in a layer at the back of an eye.
| Position | Electrical impulses in low-intensity white light | Different patterns of impulses in bright red, green and blue light | Optic nerve leaves the eye at this position |
|---|---|---|---|
| P | yes | no | no |
| Q | no | yes | no |
| R | no | no | yes |
Explain which structure of the eye this layer is. Use information from all three positions in your answer.
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.