What helps us process info contained in visual light?
Vision involves the transduction of light into _________ ___________.
How much of the cerebral cortex is involved in processing visual info?
What percentage of all sensory receptors are in the eye?
What does the eye do with the light it collects?
Converts them into nerve impulses
How much of the eye is actually visible?
How long ago did proto-eyes evolve?
600 million years ago
what are the 2 shared genetic features in all eyes?
Pax6 gene and photo receptive proteins known as Opsins
What are the 2 common disorders associated with the Pax6 mutation?
Aniridia - absence of the iris.
Peter's Anomaly - thinning and clouding of the corneas
What are the 7 accessory structures of the eye?
Eyelids, eyebrow, eyelashes, glands, conjunctiva, lacrimal apparatus and extrinsic eye muscles
What is another word for eyebrows?
What is another word for eyelids?
What is a palpebral fissure?
The space between the upper and lower eyelids
What is the supporting connective tissue where the muscles that open and close the eyelids insert?
Which eye accessory accomplishes the following: line the supraorbital arches, shade eye from sunlight, prevent perspiration from reaching the eye communication and expression
What is another term for the eyelashes?
Which eye accessory protects the eyes anteriorly from debris?
Which eye accessory lines the palpebral margins, and contain the root hair plexus which triggers the blinking effect?
-Chronic inflammation of the eyelid and eyelid margin
-Continuous burning, itching, light sensitivity and heaviness of lids
-Dandruff, crusting and cysts at margin
What's the treatment for blepharitis?
-Routine eyelid hygiene
- Topical antibiotic and anti-inflammatory applications
Normal eyelashes that are misdirected and rub against the surface of the eye causing watery, irritated, red eyes.
What is the treatment for Trichiasis?
-Electrolysis of individual lashes
-More involved focal cryotherapy of lid
Which structure connects the eyelids at the corner of the eye?
The medial and lateral canthus
Where is the lacrimal caruncle located?
Within the medial canthi
What are the small openings in the medial corners of the eyes that receive tears called?
Superior and inferior puncta
Which part of the eye contains glands that produce thick secretions (sleep)?
The lacrimal caruncle
Which eye glands secrete a lipid rich product that keeps the eyelids from sticking together and is located along the inner margin of the eyelids?
The tarsal glands
Describe the ciliary glands
They are modified sweat glands located between the hair follicles
What is the job of the lacrimal glands?
To produce tears
Where are the lacrimal glands located?
At the superior lateral portion of the eye
Name the two kinds of conjunctiva
Palpebral and bulbar (ocular)
What is the epithelial lining of the eyelids called?
The Palpebral conjunctiva
What is the palpebral conjunctiva that folds back on itself and lines the white surface of the eye?
Bulbar (ocular) conjunctiva
Where is the lacrimal gland?
Above the lateral end of the eye
What is lacrimal secretion?
Wht are the 4 sections that tears flow into?
The lacrimal puncta, the caniculi, the sac and the naolacrimal duct
How do you end up with a "runny nose" when crying?
When you tear up, tears flow across your eye and through the nasolacrimal canal into your nose
What does NLDO stand for?
Nasalacrimal duct obstruction
What are the 2 muscles of the eyelid?
Levator palpebrae superioris and the obicularis oris
What is the function of the obicularis oris?
To close the eyelid
What is the function of the levator palpebrae superioris?
Lifts the eyelid and opens the eye
List the 6 extrinsic eye muscles
Lateral rectus, superior rectus, inferior rectus, medial rectus, Inferior oblique and superior oblique.
Which eye muscle rotates the eye laterally?
The lateral rectus
Which eye muscle rotates the eye upward?
The superior rectus
Which eye muscle rotates the eye muscle downward?
The inferior rectus
Which eye muscle rotates the eye medially?
The medial rectus
Which eye muscle rotate the eye upward and laterally?
The inferior oblique
Which eye muscle rotates the eye downward and laterally?
The superior oblique
Moves eye laterally
Moves eye medially
Elevates eye and rotates it medially
Depresses eye and rotates it medially
Elevates eye and rotates it laterally
Depresses eye and rotates eye laterally