Hall: Guyton and Hall Textbook of Medical Physiology, 12th Edition
Chapter 49: The Eye: I. Optics of Vision
Test Bank
1. Most of the refractive power of the eye is located in which of the following structures?
A. The iris
B. The lens
C. The retina
D. The cornea
2. Accommodation for near vision (focusing on an object close at hand) requires which of
the following?
A. Constriction of the pupil of the eye
B. Dilation of the pupil of the eye
C. Causing the lens of the eye to have more curvature (making it fatter)
D. Causing the lens of the eye to have less curvature (making it thinner)
3. Accommodation will not occur if which of the following nerves is damaged?
A. The facial nerve
B. The vagus nerve
C. The oculomotor nerve
D. The glossopharyngeal nerve
4. Which of the following refractive problems most closely resembles presbyopia?
A. Myopia
B. Astigmatism
C. Hyperopia
D. Cataracts
5. Which of the following lenses has the greatest refractive power?
A. A 59 diopter lens
B. A 25 diopter lens
C. A 200 diopter lens
D. A 100 diopter lens
6. Myopia is usually corrected by which type of lens?
A. A convex lens
B. A concave lens
C. A spherical lens
D. A Newtonian lens
7. During the process of accommodation, to focus on an object close at hand:
A. The ciliary muscle relaxes
B. The tension on the lens resulting from the suspensory ligament increases
C. The lens becomes thinner
D. The tension on the lens resulting form the suspensory ligament decreases
8. Which of the following are paired correctly?
A. An increase in resistance to flow through the canal of Schlemm – a decrease in
intraocular pressure
B. Myopia – focal point in front of the retina
C. Hyperopia – correction by a concave lens
D. All of the above are paired correctly
9. Hyperopia usually results from:
A. An unequal curvature of the cornea
B. A lens that is too powerful for the globe of the eye
C. An eyeball that is too short
D. An increase in intraocular pressure
10. Which of the following is the most important determinant of intraocular pressure?
A. The rate of production of aqueous humor
B. The rate of production of vitreous humor
C. The stiffness of the cornea
D. The resistance to outflow of aqueous humor in the canal of Schlemm
11. The condition of hyperopia is usually corrected by:
A. A concave lens
B. A convex lens
C. A spherical lens
Test Bank
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D. A Schmidt-Cassegrain lens
12. Astigmatism usually results from:
A. An unequal curvature of the cornea
B. A lens that is too powerful for the globe of the eye
C. A lens that is too weak for the globe of the eye
D. An unequal curvature of the retina
13. Cataracts are usually the result of which of the following?
A. Denaturation of the proteins in lens of the eye
B. An eye globe that is elongated
C. An unresponsive and dilated pupil
D. Coagulation of the proteins in the lens of the eye
14. Astigmatism is usually corrected by:
A. A concave lens
B. A cylindrical lens
C. A convex lens
D. A spherical lens
15. Accommodation for far vision (focusing on an object at a distance) requires which of the
following?
A. Constriction of the pupil of the eye
B. Dilation of the pupil of the eye
C. Causing the lens of the eye to have more curvature (making it fatter)
D. Causing the lens of the eye to have less curvature (making it thinner)