Basic Science Flashcards
7 cards from real CPOA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Basic Science flashcards as text
The nasolacrimal duct drains tears into which anatomical location?
Answer: Inferior meatus of the nasal cavity
The nasolacrimal duct empties tears into the inferior meatus of the nasal cavity, explaining why crying causes nasal congestion.
What is the normal intraocular pressure (IOP) range in a healthy adult?
Answer: 10–21 mmHg
Normal IOP ranges from 10 to 21 mmHg; pressures consistently above 21 mmHg may indicate ocular hypertension or glaucoma risk.
The optic nerve exits the eye through which structure?
Answer: Optic disc
The optic disc (optic nerve head) is where the optic nerve fibers exit the globe; it contains no photoreceptors, creating the physiological blind spot.
Which layer of the tear film is produced by the meibomian glands?
Answer: Lipid layer
The meibomian (tarsal) glands secrete the outermost lipid layer of the tear film, which reduces evaporation of the aqueous layer.
Snellen visual acuity of 20/40 means the patient can see at 20 feet what a person with normal vision can see at:
Answer: 40 feet
20/40 means the patient must be at 20 feet to see what a normally sighted person can see at 40 feet, indicating reduced acuity.
The iris contains which type of muscle responsible for pupil dilation?
Answer: Dilator pupillae (radial muscle)
The dilator pupillae muscle runs radially in the iris and is innervated by the sympathetic nervous system to enlarge the pupil.
What is the primary function of the retinal pigment epithelium (RPE)?
Answer: Supporting and nourishing photoreceptors
The RPE supports the adjacent photoreceptors by recycling visual pigments, absorbing stray light, and transporting nutrients from the choroid.