THE EYE EXAM QUESTIONS AND
ANSWERS
If the eye then focuses on the words in a book, changes would occur in the eye. The
light rays would be refracted more by the lens. How does the lens refract the light more?
(1) - Answer--by becoming thicker
Which two structures control the shape of the lens?(2) - Answer--ciliary muscles
-suspensory ligaments
To form a clear image, the light rays entering the eye must focus on one structure in the
eye. Name the structure.(1) - Answer--retina
Name the common defect of the eye which causes distant objects to appear out of
focus.(1) - Answer--short-sightedness
Describe how the brain receives information about light entering the eye.(3) - Answer--
(cells in) retina sensitive to light
-impulse passes along (sensory) neurone
-(along) optic nerve
Explain how the person's eye could adjust to form a clear image of a nearer object.(6) -
Answer--ciliary muscles contract
- (so ciliary muscles have a) smaller diameter
-(so) suspensory ligaments loosen / slacken
-lens thickens or lens becomes more curved / rounded
-lens is more convergent
-lens is more convergent
Explain why a long-sighted person has difficulty seeing near objects clearly.(2) -
Answer--eye(-ball) is (too) short or lens cannot be thickened enough
-(so) light 'focuses' behind retina
Long-sightedness can be corrected by wearing spectacles. Describe how spectacle
lenses can correct long-sightedness(3) - Answer--convex / converging lens
-light rays bent / refracted (inwards) more
-light rays focused on retina
Describe the changes in the pupil and iris going from small to Big in Figure 1. Explain
how these changes occur. Refer to the changes in light level in your answer.(4) -
Answer--pupils dilate
-in dim light / low light levels
- because circular muscles (in iris) relax
- (and) radial muscles contract
ANSWERS
If the eye then focuses on the words in a book, changes would occur in the eye. The
light rays would be refracted more by the lens. How does the lens refract the light more?
(1) - Answer--by becoming thicker
Which two structures control the shape of the lens?(2) - Answer--ciliary muscles
-suspensory ligaments
To form a clear image, the light rays entering the eye must focus on one structure in the
eye. Name the structure.(1) - Answer--retina
Name the common defect of the eye which causes distant objects to appear out of
focus.(1) - Answer--short-sightedness
Describe how the brain receives information about light entering the eye.(3) - Answer--
(cells in) retina sensitive to light
-impulse passes along (sensory) neurone
-(along) optic nerve
Explain how the person's eye could adjust to form a clear image of a nearer object.(6) -
Answer--ciliary muscles contract
- (so ciliary muscles have a) smaller diameter
-(so) suspensory ligaments loosen / slacken
-lens thickens or lens becomes more curved / rounded
-lens is more convergent
-lens is more convergent
Explain why a long-sighted person has difficulty seeing near objects clearly.(2) -
Answer--eye(-ball) is (too) short or lens cannot be thickened enough
-(so) light 'focuses' behind retina
Long-sightedness can be corrected by wearing spectacles. Describe how spectacle
lenses can correct long-sightedness(3) - Answer--convex / converging lens
-light rays bent / refracted (inwards) more
-light rays focused on retina
Describe the changes in the pupil and iris going from small to Big in Figure 1. Explain
how these changes occur. Refer to the changes in light level in your answer.(4) -
Answer--pupils dilate
-in dim light / low light levels
- because circular muscles (in iris) relax
- (and) radial muscles contract