ABO NOCE Basic Opticianry Ocular Anatomy and Physiology Questions and Answers 4 — Questions and Answers
Question 1: The choroid is primarily responsible for:
- Producing aqueous humor
- Providing oxygen and nutrients to the outer retina (Correct answer)
- Maintaining intraocular pressure
- Controlling pupil size
Correct answer: Providing oxygen and nutrients to the outer retina
The highly vascular choroid supplies oxygen and nutrients to the outer one-third of the retina, including the photoreceptors.
Question 2: Bowman's layer is located between which two corneal layers?
- Epithelium and stroma (Correct answer)
- Stroma and Descemet's membrane
- Endothelium and Descemet's membrane
- Epithelium and endothelium
Correct answer: Epithelium and stroma
Bowman's layer is an acellular condensation of stromal collagen immediately beneath the corneal epithelium.
Question 3: Which cranial nerve innervates the lateral rectus muscle?
- CN III (Oculomotor)
- CN IV (Trochlear)
- CN VI (Abducens) (Correct answer)
- CN V (Trigeminal)
Correct answer: CN VI (Abducens)
The lateral rectus muscle, which abducts the eye, is exclusively innervated by the abducens nerve (CN VI).
Question 4: The retinal pigment epithelium (RPE) performs all of the following EXCEPT:
- Phagocytosis of shed photoreceptor outer segments
- Regeneration of visual pigments
- Production of aqueous humor (Correct answer)
- Absorption of stray light
Correct answer: Production of aqueous humor
Aqueous humor is produced by the ciliary body epithelium, not the RPE; the RPE supports photoreceptors through phagocytosis, pigment recycling, and light absorption.
Question 5: The blind spot in the visual field corresponds to which ocular structure?
- Fovea centralis
- Optic disc (Correct answer)
- Ora serrata
- Peripheral retina
Correct answer: Optic disc
The optic disc (where the optic nerve exits) has no photoreceptors, creating the physiological blind spot in the visual field.
Question 6: Which type of collagen is the predominant component of the corneal stroma?
- Type I (Correct answer)
- Type II
- Type IV
- Type VII
Correct answer: Type I
The corneal stroma is composed predominantly of highly organized Type I collagen fibrils, whose uniform spacing is essential for corneal transparency.
Question 7: The schlemm's canal is part of which drainage pathway for aqueous humor?
- Uveoscleral outflow
- Trabecular (conventional) outflow (Correct answer)
- Ciliary body reabsorption
- Vitreous absorption
Correct answer: Trabecular (conventional) outflow
Schlemm's canal is the final vessel in the trabecular (conventional) outflow route, collecting aqueous from the trabecular meshwork and draining into episcleral veins.
ABO NOCE Basic Opticianry Ocular Anatomy and Physiology Questions and Answers 4
The choroid is primarily responsible for: