Vision lab review

20/40 vision means you can read 40% of #20 letters on a Snellen eye chart.

false

Why is vision lost when light hits the blind spot?

The area lacks photoreceptors

Why is each eye tested separately when using the Snellen eye chart?

Visual acuity is different in each eye

ability to focus for close (under 20 ft) vision

accomadation

Presbyopia is

age-related close vision problems due to inelasticity of lens

blurred vision due to unequal curvatures of the lens or cornea

astigmatism

To which wavelengths of light do the three cone types of the human retina respond maximally? (choose all that apply)

blue, red and green

medial movement of the eyes during focusing on close objects

convergence

normal vision

emmetropia

inability to focus well on close objects (farsightedness)

hyperopia

You would expect the pupil to be dilated in which of the following circumstances? (choose all that apply)

in dimly lit surroundings in observing distant objects

What is the usual cause of color blindness?

lack of one or more of the cone types ?

nearsightedness

myopia

light bending

refraction

The dim light receptors are the____and the bright light receptors are the ______.

rods; cones

20/10 vision means you can read letters at 20 feet that "normal" eyes read at 10 feet.

true

Astigmatism is blurry vision due to unequal curvature of the lens or cornea.

true

Depth perception is the main advantage gained from binocular vision.

true

Which of the following vitamins is important for vision? (choose all that apply)

vitamin A

When more than one type of cone is stimulated,

we perceive colors intermediate to red, green, or blue.