Ocular Anatomy and Physiology Midterms P4

What are the contents and layers of the cornea?

Answer explanation

The cornea consists of five layers: the epithelium, Bowman's layer, stroma, Descemet's membrane, and the endothelium. These layers work together to protect the eye and help focus light.

What are the functions of the cornea?

Answer explanation

The cornea serves several functions: it provides most of the eye's optical power, protects the inner structures from dust and germs, and helps to focus light onto the retina for clear vision.

What is the vascular supply of the cornea?

Answer explanation

The cornea is avascular, meaning it has no blood vessels. Its nutrients come from the tear film and aqueous humor, relying on diffusion for metabolic needs.

What is the nerve supply of the cornea?

Answer explanation

The cornea is primarily supplied by the trigeminal nerve (CN V), specifically the ophthalmic branch (V1), which provides sensory innervation. This makes it highly sensitive to touch and pain.

What are the layers of the crystalline lens?

Answer explanation

The crystalline lens consists of three main layers: the anterior capsule, the lens epithelium, and the lens fibers. These layers work together to focus light onto the retina.

What are the functions of the crystalline lens?

Answer explanation

The crystalline lens focuses light onto the retina, allowing for clear vision. It adjusts its shape to change focal length, enabling us to see objects at various distances.

What are the zonules of Zinn, its parts and relations?

Answer explanation

The zonules of Zinn, or zonular fibers, are connective tissue strands connecting the ciliary body to the lens, aiding in lens shape adjustment for focusing. They consist of zonular fibers and are crucial for maintaining lens position.

What is cataract?

Answer explanation

A cataract is a clouding of the eye's lens, leading to decreased vision. It commonly occurs with aging and can be treated with surgery to restore clear vision.

What are the compositions of the aqueous humor?

Answer explanation

The aqueous humor primarily consists of water, electrolytes (like sodium and potassium), proteins, and nutrients. It helps maintain intraocular pressure and provides nutrients to the avascular structures of the eye.

What are the functions of the aqueous humor?

Answer explanation

The aqueous humor maintains intraocular pressure, provides nutrients to the avascular structures of the eye, and removes metabolic wastes, ensuring proper eye function and health.