Ocular Anatomy and Physiology Questions and Answers Flashcards
7 cards from real ABO NOCE Basic Opticianry practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Ocular Anatomy and Physiology Questions and Answers flashcards as text
The crystalline lens derives its nutrition primarily from which source?
Answer: Aqueous humor
The avascular crystalline lens relies on diffusion of nutrients — glucose and amino acids — from the aqueous humor.
Which extraocular muscle is responsible for intorsion and depression of the eye?
Answer: Superior oblique
The superior oblique muscle primarily intorts and depresses the eye, and is innervated by the trochlear nerve (CN IV).
The normal intraocular pressure range in a healthy adult is approximately:
Answer: 10–21 mmHg
Normal intraocular pressure is considered 10–21 mmHg; pressures consistently above 21 mmHg may indicate ocular hypertension.
Which structure forms the outermost fibrous tunic of the eye?
Answer: Sclera
The sclera is the tough, white outer fibrous coat that protects the inner structures and maintains the eye's shape.
The lacrimal puncta are small openings located at the:
Answer: Medial canthus of each eyelid
The lacrimal puncta are located on the medial margin of both upper and lower eyelids and drain tears into the lacrimal canaliculi.
Accommodation occurs when the ciliary muscle contracts, causing the zonular fibers to:
Answer: Relax, allowing the lens to become more convex
When the ciliary muscle contracts, tension on the zonular fibers decreases, allowing the elastic lens to round up and increase its refracting power.
The ora serrata is best described as:
Answer: The junction between the retina and the pars plana of the ciliary body
The ora serrata is the serrated anterior margin of the neurosensory retina where it transitions to the non-photosensitive pars plana.