Anatomy and Physiology of the Eye Flashcards
Axial length of the Average eye
26.5 mm
Another word for eyelids
Palpebrae
Muscle that relaxes to allow the eyelid to droop or sag
Muller’s Muscle
Size of the average bony orbit in an adult
35mm x 40mm
Reflex tears are produced by ____ and are generally caused by ____
Lacrimal glands/stimulus such as coughing, sneezing, strong smells, emotions
Glands that produce basic tear secretion
Glands of Wolfring and Krause
The three layers of the tear film in order from outermost to innermost are:
Lipid, Aqueous, Mucin
The layer of the tear film that contains the nutrients and antibiotic properties is the:
Aqueous layer
The layer of the tear film that is responsible for prevention of evaporation is the:
Lipid layer
The layer of the tear film that is responsible for holding the tears on the cornea is the:
Mucin layer
The term for the collection of the thin film of tears on the lower lid margin is:
Tear lake/Tear prism/Tear meniscus
Term for eyelids turning outward
Ectropion
Term for eyelids turning inward
Entropion
Name of the mucous membrane that lines the lids and globe of the eye
Conjunctiva
Goblet cells produce:
Mucous
Inflammation of the Conjunctiva
Conjunctivitis
The outer tunic consists of the ___, ___, and additionally the ___ and is ___
sclera/cornea/limbus/fibrous
The five layers of the cornea from outermost to innermost
Epithelium, Bowman’s layer, stroma, Descemet’s membrane, endothelium
The average power of the cornea
42-45 diopters
The cornea receives oxygen from:
Tears and blood vessels
Number of layers in the epithelium
5 to 7 cell layers
Scar tissue will form if this layer of the cornea is damaged
Bowman’s layer
If the eye is deprived of oxygen, this layer will lose more cells at a quicker pace and cause swelling of the eye
Endothelium
The canal of Schlemm encircles the ___ region, where the aqueous drains in to the trabecular meshwork
Limbal
The middle tunic is the ___ tunic and is located between the ___ and ___
Vascular/sclera/retina
The ciliary body consists of the ___ and the ___
Ciliary muscle and ciliary process
The anterior chamber is located ___
between the back surface of the cornea and the iris
The posterior chamber is located ___
between the iris and the crystalline lens
An inflammation of the iris is called:
Iritis
A difference in pupil size is called:
anisocoria
This muscle constricts to make the pupil smaller
Sphincter
This muscle dilates to make the pupil larger
Dilator
The inner tunic is the ___ and is the ___ tunic
retina/light sensitive
The aqueous humor is produced by the:
Ciliary process
If a patient experiences “floaters,” they are located here.
In the vitreous
The absence of the crystalline lens is referred to as:
aphakia
The amplitude of accommodation of the average person at birth.
15 diopters
Loss of accommodation is called
Presbyopia
The six extraocular muscles are:
Medial rectus, lateral rectus, inferior rectus, superior rectus, superior oblique, inferior oblique
Definite turning of the eye
tropia
The cornea primarily receives the nutrients it requires from the:
tear film
Primary purpose of the choroid
Supply nutrients to the retina
Photopic vision is:
Using cones in lighted conditions
Area of the retina that is responsible for finely detailed vision
Fovea
The ora serrata is located:
Outer limits of the retina adjacent to the ciliary body
The beginning of the optic nerve is located:
In the optic disk
Approximate dioptric power of the eye (both cornea and lens)
60 diopters
A drooping of the eyelid is called:
Ptsosis
The surgical removal of a portion of the iris is called:
Iridectomy
Night vision is chiefly a function of the:
Rods
