Test 203  (Ocular physiology)
1. With regard to efferent pupillary defect:
a. the pupil reacts poorly to light and accommodation

b. anisocoria is a feature

c. the affected eye has poor distant vision

d. a lesion in the sympathetic pathway is a recognized 

e. it could be caused by topical atropine application


2. The following are true about corneal sensation:
a. the sensation is greatest at the apex and diminishes 
    towards the limbus.

b. the temporal half of the cornea is more sensitive than
    the nasal half

c. the Bonnet-Cochet aesthesiometer gives quantitative 
    measure of the degree of hypoaesthesia

d. the density of nerve endings per unit area is 30 times 
    that of the epidermis

e. the sensory nerves contains unmyelinated endings 

3. The following are true about spectral sensitivity of the retina:
a. in scotopic conditions, the peak sensitivity of the eye 
    is near 500 nm

b. under photopic conditions the peak sensitivity 
    is near 555 nm

c.  in the presence of a bright yellow steady background 
     light the retina has a peak sensitivity near 440 nm to 
     a 25-Hz stimulus

d.  in the presence of a purple steady background light 
     the peak sensitivity of retina is near 540 nm to a
     25-Hz stimulus

e. in the presence of a blue-green steady background 
    light the peak sensitivity of retina is near 540 nm to 
    a 25-Hz stimulus

. 4. Regarding retinal metabolism:
a. insulin is essential for the uptake of glucose by the retina

b. anaerobic metabolism predominates 

c. the pigment retinal epithelium stores glycogen and 
    supplies the need of the retina

d. the demand of oxygen is met entirely by the central 
    retinal artery

e. the retina accumulates lactate readily.

5. The following conditions are required for rhodopsin regeneration:

b. darkness

c. splitting of all trans-retinal from the opsin

d. retinal isomerase

e. ascorbic acid

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