Correct focusing of the image on the retina in humans is achieved by changing the __________.

Difficulty in distinguishing red from green is most likely due to a defect in which cells?

A human born with nonfunctional rhodopsin would __________.

Which of the following occurs when you move from a bright area into a darkened room?

Which of the following choices is the correct order of the neural pathways that light travels after hitting the retina?

The body uses the vitamin A precursors from some foods to make a substance called retinal, which __________.

When you move an object from 15 inches in front of your eyes to 10 inches in front of your eyes, the lenses __________.

The greatest concentration of cone receptors is found at the __________.

Some sensory processing occurs within the retina of the vertebrate eye. In one type of retinal processing, a horizontal cell that receives input from a stimulated rod or cone then inhibits surrounding photoreceptors and bipolar cells. This type of processing is called __________.