retina

definition: 
A layer at the back of the eyeball that contains cells sensitive to light, which trigger nerve impulses that pass via the optic nerve to the brain, where a visual image is formed.
sentence: 
The chip captures light that enters the eye, and generates an electrical signal that is transmitted to the overlaying neural cells of the retina.
difficulty: 
easy
toefl frequency: 
1
toefl classification: