| A | B |
|---|
| neuron | A nerve cell |
| synapse | a tiny gap between neurons |
| cornea | a clear layer of the eye that light passes through |
| iris | the part of the eye that controls the amount of light that enters |
| receptor cell | a cell that receives information about the environment and starts never impulses to send that information to the brain |
| optic nerve | a bundle of nerves that carry impulses from the eye to the brain |
| auditory nerve | a bundle of nerves that carry impulses from the ear to the brain |
| cochlea | the organ in the ear that sends impulses to the auditory nerve |
| eardrum | a thin tissue in the middle ear that vibrates when sound waves strike it |
