Ocular Anatomy & Physiology Flashcards

Which layer of the cornea is responsible for maintaining corneal hydration through its pump function?

Answer: Corneal endothelium

The corneal endothelium uses Na+/K+-ATPase pumps to actively remove fluid from the stroma, maintaining corneal clarity.

The fovea centralis has the highest visual acuity because it contains predominantly which cell type?

Answer: Cone photoreceptors

The fovea centralis is packed with cone photoreceptors and lacks rods, enabling maximum visual acuity and color discrimination.

Which structure forms the boundary between the anterior and posterior chambers of the eye?

Answer: Iris

The iris separates the anterior chamber (between cornea and iris) from the posterior chamber (between iris and lens).

The optic nerve head receives its blood supply primarily from which arterial source?

Answer: Short posterior ciliary arteries

The prelaminar and laminar portions of the optic nerve head are supplied mainly by branches of the short posterior ciliary arteries.

What is the primary function of the ciliary body's pars plana?

Answer: Vitreous attachment point and surgical access site

The pars plana is a relatively avascular, flat region that serves as a safe surgical access site and anchors the vitreous base.

The ganglion cells of the retina send their axons through which structure to reach the lateral geniculate nucleus?

Answer: Optic nerve, optic chiasm, and optic tract

Retinal ganglion cell axons travel through the optic nerve, partially decussate at the optic chiasm, and continue as the optic tract to the LGN.

Which muscle is responsible for elevating the upper eyelid and is innervated by cranial nerve III?

Answer: Levator palpebrae superioris

The levator palpebrae superioris is the primary elevator of the upper eyelid and is innervated by the superior division of CN III.