Anatomy + Physiology Flashcards
The cornea is clear and must remain clear, which means that it must be ___. Have
regular cell structure, and be free from ___
- Avascular
- Scarring
The layers of the cornea from the outermost layer to the innermost layer in order are:
(List)
Epithelium (Outside), Bowman’s layer, stroma, Descemet’s membrane, Endothelium (Inside)
In a normally healthy eye, minor corneal abrasions of the cornea are generally repaired within ___
hours by mitosis and migration of fellow cells.
48
Which layer of the cornea does NOT regenerate after injury?
Bowman’s layer
Enlargement of endothelial cells is called
Polymegathism
The ___ is the transitional zone from clear, avascular cornea to the opaque sclera
Limbus
The aqueous layer, which is the middle layer of the tear film, contains ___.
Inorganic salts, glucose, and urea, as well as biopolymers, proteins, and glycoproteins.
The mucoid layer, (mucin layer, mucous layer) is produced by ____ in the ___.
- Goblet cells
- Conjunctiva
The tear film or more correctly called the precorneal tear film ___. (List)
All of the following:
1. Provides a smooth optical surface over the cornea.
2. Flushes away cellular debris and foreign matter from the cornea and conjunctival sac as well as carbon dioxide.
3. Provides nutrition for the cornea, and provides the antibacterial function of the eye.
In reality, the first refracting medium of the eye is:
The precorneal tear film
Evaluation of tear quantity and tear quality can be tested by ___. (List)
All of the following:
1. Tear break up time
2. Schirmer’s #1
3. Fluorescein, rose bengal
Sodium fluorescein is used to evaluate tear ___.
Quantity
___ stains damaged conjunctival and corneal cells.
Rose bengal
Since many cases of blepharitis are caused by dry eyes, the cornea would not be properly lubricated and contact lens wear would be uncomfortable, if not impossible ___.
Any inflammation should be resolved prior to introducing contact lenses.
The conjunctiva is a mucous membrane that runs continuously from the limbus to the lid margin. It contains goblet cells which produce the mucins for the tear layer.
(True/False)
True
On the lids, the conjunctiva is referred to as the ___ eye, it is referred to as the ___
- palpebral conjunctiva
- bulbar conjunctiva
The refractive index of the cornea is:
1.376
Inflammation of the conjunctiva is called ___.
Conjunctivitis
Symptoms of the inflammation of the conjunctiva include ___.
Pain, photophobia (light sensitivity), impaired vision, and discharge.
Eyelids are termed the ___
while opened, and they are ___.
- Palpebral aperture
- Not always the same size.
The ___ pumps tears away.
Levator muscle
___ is an eyelid that is turned inward and is often a result of muscle spasm in the lid or scarring from trauma.
Entropion
Under corneal stress, blood vessels may be seen to grow into the cornea in the area called
the limbus. This blood vessel growth is called.
Neovascularization
Crystalline lens is ___ that continues to add layers throughout life.
An onion-like structure
The ___ are two thin, elongated plates of dense connective tissue, about 2.5 cm. in length; one is placed in each eyelid and contributes to its form and support.
Tarsal plates
The fleshy caruncle is located at the ___.
Inner canthus
The retina is connected to the brain by the ___, which is not a true nerve, but tract
Optic nerve
Cones provide ___ and are more numerous in the ___
- Detail
- Macula
There are three categories of cones - according to ___. One is most sensitive to short wavelength (___), one is most sensitive to ___, and one is most sensitive to ___.
- Photopigments
- Blue
- Green
- Red
The iris is a thin vascular membrane, averaging about ___ mm horizontally and ___ mm vertically
- 11/12
- 9/10
