Eye and Vision - Eye Dissection
One method to aid understanding of anatomy is through dissection.
Since human anatomy is similar to that of other mammals, we are able to dissect other species to learn about ourselves.
The human eyes and the cow eye have many of the same structures.
A structure that differs between the human eye and the eye of many other vertebrates is a thin layer of tissue called the tapetum lucidum. This iridescent layer is deep into the retina and acts to reflect light back through the retina to increase vision in dim light. This layer is what makes some animal eyes reflective at night. Humans and most primates do not have this structure.
Forceps - Tweezers used in a laboratory setting. Often used to pick up and manipulate items.
Scalpel - A sharp, bladed instrument commonly used in a laboratory setting. Often used to cut specimens. Good at starting cuts.
Scissors - A double-bladed instrument commonly used in dissections to continue cuts or remove components.
Sclera - Part of the outer tunic made of dense, irregular connective tissue that forms the white of the eye.
Choroid - A darkly pigmented part of the vascular middle tunic deep to the sclera
Retina - The inner tunic, deep to the choroid, held in place by the vitreous humor. Functions to receive light and transmit a signal along the optic nerve.
Optic Nerve - A bundle of ganglionic axons projecting from each eye and carrying visual information from the retina to the brain.
Vitreous Humor - Transparent, gelatinous fluid in the posterior cavity that supports the retina and transmits light.
Cornea - A convex transparent structure of the sclera located at the anterior of the eye. Functions to admit light into the eye.
Iris - Located anteriorly, it is the colored proportion of the eye. Functions to control the size of the pupil. It also separates the anterior chamber from the posterior chamber in the anterior cavity of the eye.
Pupil - Opening in the center of the iris that appears black.
Lens - Layers of transparent cells that focus incoming light on the retina. Held in place by the ciliary body and separates the anterior and posterior cavities.
Ciliary Body - Forms muscular ring around the lends and secretes aqueous humor
Suspensory Ligaments - Elastic fibers that connect the lens to the muscles in the ciliary body.
Orbital Fat - Supports and cushions the eye.
Eye Muscles - Six extrinsic muscles that move the eye.