Ocular Anatomy and Physiology 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 flashcards as text
The corneal endothelium pumps fluid out of the cornea to maintain its transparency. This process requires which ion?
Answer: Sodium
The corneal endothelium uses Na+/K+-ATPase pumps driven by sodium ions to actively transport fluid out of the corneal stroma.
Which part of the optic nerve is visible during fundoscopic examination?
Answer: Optic disc
The optic disc (optic nerve head) is the only part of the optic nerve visible during fundoscopy; it appears as a pale oval disc on the retina.
Which type of photoreceptor is most sensitive to low-light (scotopic) conditions?
Answer: Rods
Rods are highly sensitive photoreceptors that function in dim light (scotopic vision) and are responsible for peripheral and night vision.
The zonules of Zinn connect the lens to which structure?
Answer: Ciliary body
The zonular fibers (zonules of Zinn) suspend the crystalline lens by connecting it to the ciliary body.
Where does the optic chiasm receive its blood supply primarily from?
Answer: Internal carotid artery
The optic chiasm is supplied primarily by branches of the internal carotid artery, including the anterior cerebral and anterior communicating arteries.
Which layer of the retina contains the cell bodies of bipolar neurons?
Answer: Inner nuclear layer
The inner nuclear layer contains the cell bodies of bipolar cells, horizontal cells, amacrine cells, and Müller cells.
What is the refractive index of the cornea?
Answer: 1.376
The refractive index of the corneal stroma is approximately 1.376, which contributes to its total refractive power of about +43 diopters.