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Question 4#

With regards to the eyes and eyelids, which statement is correct?

a. The lacrimal gland secretes tears which are bilaminar, consisting of a superficial mucoprotein layer and a deep aqueous layer
b. The lacrimal gland has three lobes
c. Tears bend incoming light before it strikes the cornea with up to 2.0 diopters of refractile power
d. The superior tarsal plate is 8-10mm in vertical height and the inferior tarsal plate is smaller at 4-6mm
e. The lacrimal sac is situated above and medial to the lateral canthus

Correct Answer is D

Comment:

The superior tarsal plate is 8-10 mm in vertical height and the inferior tarsal plate is smaller at 4-6mm. The lacrimal gland secretes a trilaminar layer of tears consisting of a deep mucoprotein layer, a middle aqueous layer and a superficial lipid layer. The lacrimal gland has two lobes, the larger orbital lobe and a smaller palpebral lobe. Tears have a refractive power of up to 0.5 diopters. The lacrimal gland is situated above and medial to the lateral canthus, whereas the lacrimal sac is medial to the medial canthus, posterior to the insertion of the canthal tendon within the lacrimal fossa.