Question 1

Which part of the human eye gives it its visible color?

Accepted Answer

Iris. The iris is the colored ring around the pupil. Its pigments determine the visible eye color. The iris muscles also help regulate incoming light.

Question 2

The image formed on the retina of a normal human eye is generally?

Accepted Answer

Real, inverted, diminished. The eye lens forms a real image on the retina. This image is inverted because a convex lens inverts images. It is usually smaller than the object for normal viewing distances.

Question 3

Which photoreceptor cells are mainly responsible for vision in dim light?

Accepted Answer

Rods. Rods are more sensitive to low light levels. They help in night or dim-light vision but do not detect color well. Cones are mainly for color and bright-light vision.

Question 4

A concave lens is commonly used to correct which defect of vision?

Accepted Answer

Myopia. Myopia makes distant objects focus in front of the retina. A concave lens diverges light rays to shift the focus back onto the retina. This helps distant objects appear clear.

Question 5

In the human eye, most of the refraction of light occurs at the?

Accepted Answer

Cornea. The cornea provides the largest bending of light entering the eye. The air-to-cornea boundary has a big refractive index change. The eye lens mainly fine-tunes focus by accommodation.

Human Eye — Set 1