Eye and Ear
Questions
DIRECTIONS: Each item below contains a question or incomplete
statement followed by suggested responses. Select the one bestresponse to
each question.261.In the surgical procedure known as LASIK, the shape of the cornea
may be flattened. This will result in which of the following?
a. Decreased refraction of light by the cornea
b. A decreased amount of light entering through the cornea
c. Conversion of the cornea from a “stationary” to an “adjustable” form of refraction
d. Maintenance of the lens in a more flattened state
e. Focusing of light on the retina at a point other than the fovea262.Retinal detachment most commonly results from which of the
following?
a. Local swelling in specific retinal layers
b. Leakage of blood from the inner retinal capillaries
c. Fluid accumulation between the retina and the retinal pigment epithelium (RPE)
d. Impaired pumping of water toward the photoreceptors by the RPE
e. Increased phagocytosis of outer segments by the RPE cells263.Visual transduction involves which of the following?
a. Inactivation of phosphodiesterase
b. Increase in cGMP levels
c. Conversion of all-trans-retinal to 11-cisretinal
d. closing of a Na+channel
e. Depolarization of the rod cell membrane264.The retinal pigment epithelium (RPE) is characterized by which of
the following?
a. The presence of the photoreceptor (rod and cone) perikarya
b. Phagocytosis of worn-out components of photoreceptor cells
c. Origin from the inner layer of the optic cup during embryonic development
d. Presence of amacrine cells
e. Synthesis of vitreous humor397Copyright © 2007 by The McGraw-Hill Companies, Inc. Click here for terms of use.