The opaque material covering the structures inside the eye is called the
a. iris. c. pupil.
b. lens. d. sclera.
D
The eye is approximately 1 inch in diameter and has three continuous layers: 1) a tough, outer, fibrous tunic called the sclera; 2) a middle, vascular tunic called the choroid; and 3) the innermost layer which contains the retina. The outer tunic consists of the transparent cornea on the outer portion, which is continuous with the sclera, an opaque material that appears white and covers the structures inside the eye. The cornea is a nonvascular, transparent surface that covers the iris and the pupil. The iris provides a distinctive color for the eye and functions as a diaphragm, varying the opening at its center, the pupil. The pupil regulates the amount of light entering the eye. The lens is a biconvex disc located just posterior to the pupil and changes shape in order to refract light from various focusing distances.
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a. decreased pCO2 b. decreased PaO2 c. decreased K+ level
You have just admitted Mrs. DeLuca. You should not leave her room until
A. the bed is in the high position. B. she knows how to work the television. C. you show her how to use the call signal. D. she provides a urine specimen.