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17 Cards in this Set
- Front
- Back
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1. Which retinal layer receives nutrients from both the retinal and choroidal vasculature?
A. the inner nuclear layer B. the inenr plexiform layer C. the outer nuclear layer D. the outer plexiform layer E. the photoreceptor layer |
D. The middle limiting membrane w/i this layer is said to be the demarcation of the extent of the retinal nutrition
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2. Normally the dye used in florescein angiography cannot pass form the choroid into the retinal tissue b/c:
A. zonular occludens is found in the vessels of the choriocapillaris B. Bruch membrane acts a barrier to blood flow C. the retinal pigment epithelium (RPE) contains zonula occludens D. the external limiting membrane provides a barrier |
B. b/c iris crypts allow aqueous access into iris stroma, it is important that the iris capillaries do not allow large molecules to pass into the stroma and change the aqueous composition.
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11. The role parasympathetic innervation plays in the nasolacrimal system includes:
A. constriction of meibomian pores B. increase in goblet cell population C. increase of secretion from the lacrimal gland D. contraction of the lacrimal sac |
C. The parasymp. system has a role in production of meibomian material and in stimulating the goblet cell to secrete
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25. Where do the preganglionic parasympathetic fibers that carry the information resulting in accom. originate?
A. the Edinger-Westphal accessory third nerve nucleus B. the superior colliculus C. the ciliary ganglion D. the frontal eye fields E. the superior cervical ganglion |
A. The postganglionic fibers originates in the ciliary ganglion; the postganglionic sympathetic fibers originate in the superior cervical ganglion
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Q. Where do the postganglionic parasympathetic fibers that carry the information resulting in accom. originate?
A. the Edinger-Westphal accessory third nerve nucleus B. the superior colliculus C. the ciliary ganglion D. the frontal eye fields E. the superior cervical ganglion |
C. the ciliary ganglion
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Q. Where do the postganglionic sympathetic fibers that carry the information resulting in accom. originate?
A. the Edinger-Westphal accessory third nerve nucleus B. the superior colliculus C. the ciliary ganglion D. the frontal eye fields E. the superior cervical ganglion |
E. the superior cervical ganglion
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35. Parasympathetic stimulation of the ciliary body will result in:
A. release of tension in the zonules B. a posterior movement of the suprachoroid C. a decrease in ciliary muscle tone D. an increase in the lens diameter |
A. ciliary muscle contraction is stimulated by the para. and results in anterior movement of the choroid, a decrease in the lens diameter, and a release in zonular tension.
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36. What best describes the role of the iris in the blood-aqueous barrier?
A. although the iris capillaries are fenestrated, a diaphragm covers the fenestrations B. the junctions in the anterior border layer prevent entrance of the aqueous into the iris C. the thick-walled vessels prevent absorption of aqueous into the arteries D. the nonfenestrated iris capillaries contain zonula occludens |
D. The anterior border layer contains openings (crypts) that allow access of aqueous into iris stroma; the connective tissue around the blood vessels is for support
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44. The receptive field of a retinal ganglion cell:
A. is made up of corresponding points in the visual field of both eyes B. includes only the bipolar cells in synaptic contact w/ the ganglion cell C. can be expanded by horizontal cell involvement D. includes only the bipolar an amacrin cells in synaptic contact w/ the ganglion cell |
C. A retinal ganglion cell cannot be activated by a stimulus in the visual field of the other eye; the receptive field for a ganglion cell includes all retinal cells that influence that cell, whether directly or indirectly
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45. A lesion involving the right optic tract will most likely result n:
A. left homonymous hemianopia B. a congruent right homonymous hemianopia C. a rerimacular scotoma D. a bitemporal loss |
A. b/c the optic tract is of such a small diameter, damage often involves all the fibers causing a hemianopia; damage to the right postchiasmal pathway will affect teh left side of the visual field
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46. Which retinal area will a target seen in the superior temporal field by the left eye be imaged?
A. inferior nasal B. inferior temporal C. superior nasal D. superior temporal |
A. Targets in superior field are "seen" by the inferior retina, those in nasal field are "seen" by the temporal retina.
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47. Which extraocular muscle causes elevation w/ the eye in right gaze?
A. right superior rectus B. left superior rectus C. right superior oblique D. left superior oblique |
A. In right gaze, the right eye is abd. and the superior rectus is the elevator; the left eye is add., and the inferior oblique is the elevator
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48. What muscles are the yoke muscles resulting in depressed left gaze?
A. right superior rectus and left inferior oblique B. right inferior oblique and left superior rectus C. right superior oblique and left inferior rectus D. right inferior oblique and left inferior oblique E. right superior oblique and left inferior oblique |
C. In left gaze, the right eye is add., the depressor is the superior oblique, and the left eye is abd.; the inferior rectus is the depressor
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49. Which extraocular muscle(s) cause(s) intorsion?
A. superior oblique B. inferior rectus C. superior rectus D. A and C |
D. The two superior muscles cause intorsion
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50. What mechanism accounts for the coordination of the yoke muscles in left-right gaze?
A. fasciculus of the oculomotor nerve B. internuclear neurons in the abducens nucleus C. the geniculocalcarine tract D. internuclear neurons in the oculomotor subnucleus for the medial rectus |
B. The internuclear neurons w/i the nucleus of CN VI communicates w/ the nucleus controlling the opposite medial rectus muscle via the medial longitudinal fasciculus for the coordination of binocular right-left vision
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51. How does the extraocular muscles differ from the typical vertebrate striated muscle?
A. extraocular muscle does not contain twitch fibers, but skeletal muscles does B. extraocular muscle has fewer muscle fibers/motor neuron than does skeletal muscle C. extraocular muscle has a different banding pattern than that of striate muscle D. extraocular muscle is more easily fatigued than the skeletal muscles |
B. Extraocular muscle has only 7 to 10 fibers/neuron, but extraocular muscle does contain twitch fibers and is more fatigue resistant than skeletal muscle.
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52. Hering's law of equal innervation refers to the:
A. equal innervation necessary for conjugate yoked eye movements B. torsion movements that maintain the retinal raphe parallel to the horizon C. innervation supplied to antagonist of an extraocular muscle D. relation b/t the physiologic orgion and the anatomic orgin |
A. Hering's law of equal innervation refers to the equal innervation to yoke muscles.
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