EYES

Which structure of the eye maintains its shape and protects inner structures? 

 

• Cornea

• Lens

• Sclera 

• Retina 

Answer explanation

Answer: C. Sclera 

Rationale: The sclera, or “white of the eye,” maintains shape and provides protection. The cornea refracts light, the lens focuses it, and the retina receives visual images. 

The cornea contributes approximately how much to light refraction? 

 

• 20% 

• 40% 

• 60%

• 80% 

Answer explanation

Answer: D. 80% 

Rationale: The cornea provides about 80% of the eye’s light refraction, allowing focused images on the retina. 

The iris controls which of the following functions? 

 

• Drainage of aqueous humor

• Size of the pupil 

• Shape of the lens 

• Eye lubrication 

Answer explanation

Answer: B. Size of the pupil 

Rationale: The iris adjusts the pupil to regulate the amount of light entering the eye. 

The conjunctiva is the site of which common infection? 

 

• Blepharitis 

• Conjunctivitis 

• Keratitis 

• Uveitis 

Answer explanation

Answer: B. Conjunctivitis 

Rationale: Conjunctivitis (“pink eye”) affects the conjunctiva, the membrane covering the sclera and inner eyelids. 

Presbyopia commonly occurs after age 40 due to: 

 

• Thickening of the cornea

• Weakening of the optic nerve 

• Decreased lens elasticity 

• Retinal detachment 

Answer explanation

Answer: C. Decreased lens elasticity 

Rationale: The lens loses elasticity with age, causing difficulty focusing on near objects (presbyopia). 

Ptosis can be caused by which neurologic disorder? 

 

• Parkinson’s disease 

• Myasthenia Gravis 

• Multiple sclerosis 

• Bell’s palsy 

Answer explanation

Answer: B. Myasthenia Gravis 

Rationale: Ptosis (drooping eyelid) is seen in Myasthenia Gravis due to muscle weakness. 

A white or gray ring around the cornea is called: 

 

• Xanthelasma 

• Arcus Senilis 

• Entropion 

• Chalazion

Answer explanation

Answer: B. Arcus Senilis 

Rationale: Arcus Senilis results from lipid deposits; common in aging and high cholesterol. 

Glaucoma results from: 

 

• Retinal detachment 

• Infection of the eyelid 

• Inflammation of the uveal tract 

• Increased intraocular pressure damaging the optic nerve 

Answer explanation

Answer: D. Increased intraocular pressure damaging the optic nerve 

Rationale: Glaucoma increases IOP, leading to optic nerve damage and potential blindness. 

Which population has the highest risk for glaucoma? 

 

• Hispanic 

• African American 

• Caucasian 

• Asian 

Answer explanation

Answer: B. African American 

Rationale: African Americans have four times higher risk for glaucoma. 

The most common type of glaucoma is: 

 

• Angle-closure 

• Open-angle 

• Secondary 

• Congenital 

Answer explanation

Answer: B. Open-angle 

Rationale: Primary open-angle glaucoma develops slowly and is the most common form.