Optometric Technician Certification | Questions and Answers(A+ Solution guide)

Cornea - The clear, transparent portion of the outer covering of the eyeball which covers the iris and pupil. It is the first refracting body of the eye and yields a focal power of approximately 43 diopters. Sclera - The tough white covering of the eyeball often referred to as "the white of the eye" Pupil - The opening in the iris that allows light to enter the eye Iris - The color part of the eye that opens and closes (dilates and constricts), controlling the amount of light entering the eye by changing the size of the pupil. Conjunctiva - A clear covering that lines the outer surface of the eyeball and covers the inner side of the eyelids Lens - A transparent and clear body located inside of the eye, towards the front. It brings rays of light to a sharp focus on the retina. It is also known as "the crystalline lens". Muscles surrounding the lens cause the eye to change focus or accommodate. Vitreous Humor - The clear, gel-like material located toward the back of the eyeball that maintains the shape of the eye Retina - The innermost membrane lining located at the back of the eye. It is comprised of nerve fibers and functions like the film in a camera. Optic nerve - A bundle of nerve fibers that connects each eye to the brain and transmits images from the retina to the brain Macula - The most sensitive part of the retina that is about the size of a pinhead and is where our most detailed vision occurs.